[[quoteright:300:http://static.tvtropes.org/pmwiki/pub/images/percy_jackson_book_1.jpg]]

->''If you're a normal kid, reading this because you think it's fiction, great. Read on. I envy you for being able to believe that none of this ever happened. But if you recognize yourself in these pages-if you feel something stirring inside- stop reading immediately. You might be one of us. And once you know that, it's only a matter of time before they sense it too, and they'll come for you.''

''Percy Jackson and the Olympians'' is an UrbanFantasy series by Creator/RickRiordan based on [[ClassicalMythology Greek mythology]]. The SequelSeries, ''Literature/TheHeroesOfOlympus'', has its own page. Its first four books,''The Lost Hero'', ''The Son of Neptune'', ''The Mark of Athena'', and ''The House of Hades'', have already been released. The first two [[TheFilmOfTheBook book movies]], ''Percy Jackson & the Olympians: The Lightning Thief'', and ''Percy Jackson: Sea of Monsters'' have been released.

In the books the Greek gods have moved to the United States, and their home, Olympus, is now located at the 600th floor of the Empire State Building. They have many [[HalfHumanHybrid demigod]] children with mortal humans. Unfortunately, these demigods [[WeirdnessMagnet attract mythological monsters]], so they must travel to a safe haven in Long Island, New York, called "Camp Half-Blood", and learn to fight. The books get progressively DarkerAndEdgier throughout the series as a war with the Titans approaches.

The books in the main series are:

* ''The Lightning Thief''
* ''The Sea of Monsters''
* ''The Titan's Curse''
* ''The Battle of the Labyrinth''
* ''The Last Olympian''

There are also four companion books:

* ''The Demigod Files'': Includes three short stories and information about Camp Half-Blood.
* ''The Ultimate Guide''
* ''Demigods and Monsters''
* ''The Demigod Diaries'': Includes three additional short stories as well as a short story by Rick Riordan's son, Haley

'''Please add all new character tropes to the [[Characters/PercyJacksonAndTheOlympians Character Sheet]].'''

Now has a [[http://tvtropes.org/pmwiki/crowner.php/BestEpisode/PercyJacksonAndTheOlympians Best Installment Crowner]].
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!!This series provides examples of:

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[[folder:A-E]]
* ABirthdayNotABreak: Percy forgets his [[DangerousSixteenthBirthday sixteenth birthday]].
* AbusiveParents: Many gods neglect their children. It's the biggest reason why there ''is'' a Titan army. There are kids who are ''never'' claimed. They get stuck at the Hermes cabin.
** [[spoiler: Nemesis, God of Balance and Revenge,]] to Ethan. The one time they meet, she blinds his left eye with the promise that he would [[spoiler: bring balance to the world once again]].
** You've got Kronos, Father of the gods, who ate his own children to keep them from rebelling against him.
** In the first book, Percy's stepfather, "Smelly" Gabe, treats both Percy and his mom like dirt. Thankfully, [[spoiler: Sally Jackson uses the Medusa head from Percy on Gabe, sells the statue, and gains enough money from it to go into writing]].
** [[spoiler: This either solidifies Sally as a BadAss MamaWolf, or a KarmaHoudini - she never really gets called out on sentencing [[FateWorseThanDeath a sentient being to becoming a statue]] [[AndIMustScream that probably remains conscious and thinking until it's broken.]]]]
*** [[spoiler: Actually, in the last book, there's a scene where the Titan army is at Medusa's "garden gnome" shop and it describes how some of the statues (including one that used to be Grover's Uncle Ferdinand) are broken, but there's no indication that the break did anything to "release" the person or creature from the stone prison, so it would appear that once they've been turned to stone, there's no coming back and - for all intents and purposes - they are dead.]]
* AbusivePrecursors: The Titans.
* AchillesHeel: Figuratively and literally. Taking a dip into the River Styx enables you to become invincible so no weapon will harm you, except at a tiny spot somewhere on your body. Along with Achilles' actual heel, [[spoiler: the final book has two--a spot on Percy's back and a spot near Luke's armpit]]. Additionally, the tiny weak spot isn't the only AchillesHeel of taking a bath in the Styx. While you TakeALevelInBadass in addition to becoming invincible, you do so basically by turning your body UpToEleven, meaning you need especially long periods of rest in-between fights. Meaning that if someone throws enough {{Mooks}} at you, you will drop from exhaustion ''faster'' than a normal person.
** In addition, it is implied that bathing in the Styx amplifies the bather's own personal "fatal flaw"--you become heavy with one emotion (such as pride) that can be used against you. This is somewhat subverted in that [[spoiler:the weakness that Percy has, personal loyalty, doesn't actually link in to a defeat in the finale]].
* AchillesInHisTent: [[spoiler: Clarisse]] in ''The Last Olympian''. [[spoiler: Hades]] as well.
* ActionGirl: Tons. Annabeth, Thalia, Bianca and Zoe to name a few. Just as helpful as the boys, usually.
* AffablyEvil: Geryon. He makes omelettes from the eggs of endangered species, slaughters the cattle of the sun, sells to Kronos' army, and enslaves Nico. On the other hand, he doesn't interfere with quests, holds barbecues for his captives, and gives people a grand tour of his ranch.
-->'''Grover:''' You slaughter Apollo's sacred cows?! YouMonster!
-->'''Geryon:''' [[DeadpanSnarker What gave it away, my three bodies?]]
* AFormYouAreComfortableWith: Most of the Gods and Goddesses upon their first appearances. Occasionally subverted when they decide to show their true forms, but Percy usually doesn't look when they do this.
** He doesn't look because [[YouCannotGraspTheTrueForm looking on the true form of a god is fatal to normal people]], and probably has the same effect that opening the Ark in ''RaidersOfTheLostArk'' does.
* AllMythsAreTrue: If it showed up in any Greek mythological story, it's not a myth. And it probably wants to kill you. When Percy asks about whether or not {{God}} exists in the first book, he's told by Chiron that he would be getting "metaphysical". Apparently ''the Olympians'' don't know if He exists any more than we do.
** TheKaneChronicles, the other YA Fiction series by Rick Riordan actually taking this a step further, suggesting not only that all Greek myths are true (the series ties in to the Percy Jackson series) but by also stating all Egyptian gods are real. Moses of the Abrahamic religions is also mentioned.
** TheKaneChronicles had a line about the Faust Family being deeply involved with supernatural whatsits as well, so it can be assumed European fairy tales might just be fair game as well.
* AllThereInTheManual: ''The Demigod Files'' and ''Demigods and Monsters''. (The former is significant in that it explains a lot of the "dragon" business in ''TheHeroesOfOlympus'' and gives Clarisse CharacterDevelopment.)
* AlwaysSaveTheGirl: Aphrodite urges this course of action on Percy in ''The Titan's Curse''.
* AmazonBrigade: The Hunters of Artemis.
* AnnoyingYoungerSibling: Nico to Bianca, [[spoiler: Tyson]] to Percy [[SubvertedTrope at first]].
** Apollo to Artemis, no matter what he says in most traditions she was born first.
* ApocalypseMaiden: [[spoiler: Thalia]] in ''The Titan's Curse''.
* ArmyOfTheAges: The fortress of the Greek god Hades is guarded by dead soldiers from all of history: Skeletal Roman legionnaires with spears are joined by undead US Marines with assault rifles.
* ArsonMurderAndJaywalking: The cannibals in ''The Sea of Monsters'' are: Marrow Sucker, Skull Eater, and... Joe Bob.
--> '''Dionysus playing Pac-Man:''' The world will fall, the gods will die, and I will never achieve a perfect score on this stupid machine!
** The punishments in the Underworld:
--->"Even from far away, I could see people being chased by hellhounds, burned at the stake, forced to run naked through cactus patches or [[CrowningMomentOfFunny listen to opera music.]]"
*** That depends: there is some opera that might be truly dreadful to listen to.
* AscendedExtra: Hestia, who appears in the first book stoking the campfire at Camp Half-Blood, but Percy doesn't find this out until ''The Last Olympian''.
* AttentionDeficitOohShiny: All demigods have ADHD, which is a sign of their battlefield reflexes and greater sensory perception. The disorder is handled well, though, since Riordan's son has ADHD and he knows what he's talking about.
* AttendingYourOwnFuneral: Percy is launched out of a forge in Mount Saint Helens in ''Battle of the Labyrinth'' and wakes up on Calypso's island. He spends the equivalent of two weeks there. Hephaestus then enchants a raft that allows Percy to drift back to Camp Half-Blood. When he arrives, he walks in on his own funeral as the campers prepare to torch his shroud.
* AuthorAvatar: Percy is basically the representation of the author's son who has ADHD and dyslexia. It seems the gods do as well.
* AwesomeButImpractical: [[spoiler: After taking a dip in the River Styx, Percy [[TookALevelInBadass takes a major level in badass]], but has to rest after almost every fight he gets into.]]
* BackFromTheDead: [[spoiler:Thalia]] and a few others.
* BadassArmy: The demigods as well as Kronos's army of monsters.
* BadassBookworm: Annabeth most prominently, but her dad and Daedalus count too.
* BadassNormal: Mr. Chase, Percy's mom and Paul Blofis.
* BarrierMaiden: Thalia in tree form.
* BeethovenWasAnAlienSpy: It seems that most any legendary figure in the history of western civilization who did something important was a demigod: George Washington was the [[SpontaneousGeneration brainchild]] of Athena (and [[HistoricalInJoke it must have had something that helped the colonists win the American Revolutionary War]]), Harriet Tubman was a daughter of Hermes, and [[StupidBroomstickHitler Hitler was a son of Hades]].
** Oh, and by the way, Edward Teach (also known as Blackbeard) is a son of Ares. He and his crew have been trapped in Circe's cage as guinea pigs for about 300 years, so when they are turned back into humans by Percy's vitamin pill, they take no hesitation in ransacking the isle as revenge.
* BelligerentSexualTension: Between Percy and Annabeth.
* TheBermudaTriangle: With mythological sites that used to be around Greece and Rome now located in America, this location got to take the title of the Sea of Monsters from the Mediterranean Sea.
* BestHerToBedHer: This seems to be how romance works at Camp Halfblood: "If a girl keeps trying to kill you it means she's into you."
* BettyAndVeronica: Subverted with Annabeth and Rachel; both are very nice girls who like Percy (the Archie). If one had to get technical, either one could be considered the Betty or the Veronica; Annabeth could be the Veronica, since she's meaner and more violent (but not terribly) than Rachel, who is almost always polite and well-mannered (since she's from upper class) and because of that could be considered the Betty. Or one could consider Annabeth to be the Betty, since she's known Percy for longer, is best friends with him, and is blonde, while Rachel, in true Veronica fashion, becomes friends with Percy later on and interferes in Percy and Annabeth's budding romantic relationship, albeit unintentionally. Both girls are considered to be very good-looking by others, furthering the justification.
* BigApplesauce: It's where Mount Olympus is located, and Percy's home town.
* BigBad: Kronos
** Though as he is SealedEvilInACan for the first four books, each of those books also has its own BigBad.
*** ''The Lightning Thief'': [[spoiler: Luke.]]
*** ''The Sea of Monsters'': [[BigBadEnsemble Polyphemus and]] [[spoiler: Luke.]]
*** ''The Titan's Curse'': General [[spoiler: Atlas.]]
*** ''Battle of the Labyrinth'': King Minos and [[spoiler: Kronos himself, who is finally free via a half-blood host.]]
* BigDamnHeroes:
** Quite often in the books, especially in ''The Last Olympian''. Special mention should probably go to Hades, the Ares Cabin, and the Party Ponies, who get three moments in the series.
** This is Mrs. O'Leary's sole reason for existing. Well, this and [[PluckyComicRelief Comic Relief]].
* BigNo: Several.
** Kronos. Not so much dragged out, but it was in allcaps, and the idea remains the same.
** Tantalus' "Nooooooooo!" in The Sea of Monsters after Dionysus sends him back to the Underworld.
** Sisyphus in The Demigod Files. "NOOOOOOO!"
** Zoe when Atlas is about to stab Artemis.
** [[spoiler:Atlas being returned to his chains.]] "NOT AGAIN!"
* BlackAndGrayMorality: Help the Gods who are often [[JerkWithAHeartOfGold jerkasses]] and sometimes cause problems, or serve a [[BigBad Titan]] who [[AbusiveParents devoured his own kids]] and uses humanity as a source of [[GladiatorGames cheap amusement]] or as [[ToServeMan a snack]].
* BlessedWithSuck / CursedWithAwesome: Having a perfect understanding of ancient Greek, and whether you are willing to tolerate having ADHD as a side effect of your supernatural combat instincts. And then there's all the monsters you attract, especially if you carry a cell phone
** Grover has managed to locate half-bloods on three separate occasions. Unfortunately, all of them have been children of the Big Three, and thus the most likely to die.
* BlondBrunetteRedhead: The three major females in the book: Annabeth, Thalia, and Rachel.
* BoundAndGagged: Several times in the book series, [[FanService for the enjoyment of the fans]].
* {{Bowdlerise}}: Anyone should know that Greek mythology is not exactly kid-friendly, so the author had to intervene. Random Example: It's stated Kronos cut Uranos "to bits". Somewhat unprecise - technically it was only [[GroinAttack two bits, the bits Uranos loved most and the rest of Uranos.]]
* BreakTheCutie: Nico, Thalia, Luke, and Annabeth.
* BringThemAround
* BrokenBridge: Inverted. In the fifth book, Percy destroys the Williamsburg Bridge in an attempt to stop Kronos's army.
* ButtMonkey: Humanity in-universe, or at the very least Westerners. Whether it's tourists being turned to stone by Medusa, children being lured into a [[LotusEaterMachine Lotus Eater Machine]] for eternity, or innocent shoppers being stretched to death or hacked up by Procrustes, it sucketh verily to be a human in the Percy Jackson universe.
** And if humans are lucky enough to avoid those fates, then they usually end up being the innocent victims of divine temper-tantrums, cosmic playthings for the gods, and in general are oblivious to the world around them.
* CallingTheOldManOut: In a series saturated with ParentalAbandonment, you know this is coming. It's [[spoiler:Luke]]'s whole reason for wanting to tear down Olympus in the first place.
--> '''Hades to Kronos:''' ''"And if there's one thing we can agree on, it's that you were a TERRIBLE father."''
* TheCallKnowsWhereYouLive: Half-bloods smell like lunch to monsters.
* [[CampUnsafeIsntSafeAnymore Camp Unsafe Isn't Safe Anymore]]: In the second Percy Jackson book, Percy Jackson and the Sea of Monsters, Camp Half Blood is "no longer safe" because someone has poisoned Thalia's pine tree, which usually keeps the camp safe from outside monsters. However, the camp was never safe from anyone on the inside who wanted to hurt anyone else on the inside, as demonstrated by the ending of the first book.
* CannotSpitItOut: A staple of the series; if anyone has any sort of vital information, they ''will'' hold it back for longer than necessary. Most often they have their reasons for it, but it still gets very noticeable after a few books. And when they ''do'' try to tell straight away, they're generally interrupted by someone or something else before they can get to the point. Of course, this is based on Greek mythology so it's not surprising.
* CelestialBureaucracy: The Underworld, all the way. You know the Ancient Greek tradition of putting a coin in the dead's mouth to help them pay their passage across the River Styx? Charon charges people's ''credit cards''. And if you're a kid and don't have one? Well, you're kind of screwed.
** Messed with in the movie. Charon takes drachma like in the original myths. When Grover tries to pay him with U.S dollars, he BURNS THE MONEY. The scene is even complete with a recession joke.
* CerebusSyndrome
* ChangelingFantasy
* ChekhovsGunman: Remember Circe's assistant in ''TheSeaOfMonsters''? Now read the second book of the second series. Also, that little girl at the campfire in ''the very first book'' turned out to be rather important...
* TheChessmaster : Kronos
* CirclesOfHell: What did you expect? This is Greek mythology. Within the Underworld, there's the Isles of the Blest at the top, Elysium below that (or encircling them), the most widely populated Asphodel Fields, and then the Fields of Punishment.
** Then there's also the fact that you get special punishment from Hades himself if you're sufficiently bad.
*** It's implied your soul get's sewn into his clothes a little bit later.
* CoolSword: Riptide and Backbiter. Also [[spoiler:Nico's sword made out of Stygian iron.]]
* CoolAndUnusualPunishment: Percy mentions being forced to listen to opera music for eternity as one of the tortures inflicted in the Fields of Punishment.
* CorruptHick / CorruptCorporateExecutive: Geryon makes omelettes out of the eggs of endangered species, slaughters the sacred sun cattle, has contracts to the Titan army, and tries to sell Nico to Luke.
* CorruptCorporateExecutive: One of the spirits that Percy, Annabeth and Grover see getting stopped by a security guard at the Underworld security checkpoint in the first book is one that Percy recognizes as a televangelist who had promised to raise millions of dollars for orphanages....but was then caught embezzling it and pocketing it for himself to spend on his own mansion. He was then killed in a police chase after his Lamborghini for the Lord ran off a cliff.
* CreatorProvincialism: The United States is literally the current center of western civilization. Canada is mentioned, but only because it's where Laystrigonian giants are from.
** In the sequel, Canada is featured more.
* CrossoverCosmology: The Roman god Janus appears in the fourth book. WordOfGod said in an interview that the Roman gods exist but they are younger than the Greek gods. Riordan's other novel series, ''The Kane Chronicles'', which features Egyptian gods, also takes place in the same universe.
** ''TheHeroesOfOlympus'' takes this a step further, suggesting that the gods ''do'' go around in their Roman aspects and there is an opposite camp for their children.
*** The camp is either Camp Jupiter or New Rome, depending on who talks about it. [[spoiler: Percy gets sent there with [[LaserGuidedAmnesia God-Guided Amnesia]] as an unwilling participant of Hera trying to the two together.]] Also, the gods morph depending on who's talking to them (Zeus for a Greek, Jupiter for a Roman). [[spoiler: Unless the two sides are in a war, then the gods are debilitated and constantly switching between the two forms.]]
* CruelAndUnusualDeath: [[spoiler:Bianca]] is electrocuted inside a giant bronze automaton in New Mexico. [[spoiler:Zoe]] is killed by a combination of dragon poison and her father on Mount Tamalpais. But the laurels definitely go to [[spoiler:Silena]], who's facially disfigured by the acid breath of a giant, two-hundred-foot-long worm that and gets launched into the pavement.
** [[spoiler:Silena]]'s death doubles as FridgeHorror when you think about whose child she is. A daughter of [[spoiler:Aphrodite]] essentially having her face melted with acid? That would be like Annabeth losing all of her intelligence and dying because of it. Or Percy drowning and dying!
* CrystalDragonJesus: Consciously averted. Percy initially equates the concepts of {{God}} and the Greek gods, but Chiron is quick to point out that God is "metaphysical" and therefore in a different category from the Olympians.
* CueTheFlyingPigs: A particularly dangerous one is the Clazmonian Sow who lives around Cloudcroft, New Mexico.
* DangerousSixteenthBirthday: Percy's prophecy.
* DarkerAndEdgier: The series gets progressively darker with each following book, finally capping off with the deaths of [[spoiler:Silena, Beckendorf, Luke and more]] and quite a few [[TearJerker tearjerkers]] in The Last Olympian.
* DarkSecret: [[spoiler: Zoe]] is the daughter of a titan general, Kronos' right hand. Also she was the mastermind behind at least one of "Hercules'" great victories; it's implied she may have helped him with others.
* DeadpanSnarker: Pretty much ''everyone'' is a deadpan snarker (though Percy probably gets the most in). The chapter titles are almost always deadpan snark in some way: "I Accidentally Blow Up My Pre-Algebra Teacher" is the first.
* DeadPersonConversation: With King Minos, [[spoiler:Bianca]], Achilles. Nico di Angelo does this regularly being the son of [[spoiler: Hades]]
* DeathIsCheap: The monsters and [[spoiler:Luke/Kronos]].
* DefangedHorrors
* DefrostingIceQueen: Zoe, Thalia, and arguably Annabeth.
* DespairEventHorizon: Percy has one in ''The Last Olympian'' when [[spoiler:Silena [[HeroicSacrifice dies]] [[RedemptionEqualsDeath after revealing]] she was TheMole]], Rachel cuts him off, Annabeth is angry at him over Luke and Rachel, his parents are caught in the cursed sleep, Olympus seems about to fall, and he'd seen the cruel acts of Zeus, Hades, and Hermes. He almost [[spoiler:lets Hope out of Pandora's Box and surrenders]], but after remembering some [[TrueCompanions inspiring words]] from Chris Rodriguez and Nico, he instead gives [[spoiler:the jar]] to Hestia and fights on stronger than ever.
* [[DidYouJustFlipOffCthulhu Did Rachel Just Throw a Blue Plastic Hairbrush at Kronos?]]
** Also, from Maria di Angelo:
-->Zeus is ''un imbecile.''
* DidYouJustPunchOutCthulhu: It took all the Olympians, Poseidon's army, a cross country trip through the USA and [[LittleHeroBigWar the entirety of the final book]] but they ''did'' defeat [[spoiler: Typhon the Storm Giant.]]
** [[spoiler: At the end of the first book, 12-year-old Percy, with barely any training, manages to beat Ares, the several-thousand-year-old ''god of war''.]]
* DisabilitySuperpower: All half-bloods have ADHD, which enhances their battle awareness, and dyslexia, which is caused by their brains being hardwired for ancient Greek.
* DisproportionateRetribution: Luke betrays his friends, humanity and the gods just to get back at his dad.
* DistractedByTheSexy: Percy is reduced to speaking gibberish when speaking to Aphrodite in ''The Titan's Curse''. He also says she's too beautiful to describe in his narration.
* DivineParentage: Of course.
* DoesThisRemindYouOfAnything: Percy says he is expecting the Underworld entrance to be pearly gates or a black portcullis. The actual result is...an airport security checkpoint. There's an EZ Death line, as well as two Attendant on Duty lines that ''crawl'' at a very slow rate. Also, the spirits in the waiting room have been there for a few hundred years.
* DoomyDoomsOfDoom: Chapter 14 in the second book is titled "We Meet the Sheep of Doom" on Polyphemus's island. These are sheep who rush and kill a poor defenseless deer right in front of Percy and Annabeth. A deer who goes from being a living creature to being a pile of bones picked entirely clean in under two seconds.
* DownInTheDumps: In book three, Percy and crew wander into the "junkyard of the gods" in Yuma Claw, Arizona and end up setting off a giant automaton. Naturally.
* DramaticThunder: It tends to happen a lot thanks to Zeus, so naturally it's [[{{LampshadeHanging}} lampshaded.]]
* DreamSpying: All. The. Time.
* DrivesLikeCrazy: The Gray Sisters. Given they're all fighting over that one eye while behind the wheel, it's amazing they can avoid getting into any accidents.
** Thalia [[spoiler:driving the airborne sun chariot in schoolbus form.]] Mainly due to her [[{{Irony}} Acrophobia]]. She can drive well on land, though.
*** She torches a New England village flying it, and also doesn't land smoothly enough at Camp-Half Blood, prompting Apollo to say they should look and hope they haven't burned up anyone important.
* DodgeBallIsHell: A bit more literally than you might think at the beginning of the second book.
* DuelToTheDeath: Happens so often, you lose count.
* DueToTheDead: Heroes are cremated with funeral shrouds embroidered to indicate their divine parentage and just what made them great.
-->''"We need a shroud. A shroud for [[spoiler:the son of Hermes]]."''
* DyingMomentOfAwesome: Anyone who dies goes out with a [[DyingMomentOfAwesome really, really loud bang]].
* EarlyBirdCameo: [[spoiler: Hestia]]. Pay attention to that little girl at Camp Half-Blood in "The Lightning Thief".
** [[spoiler: Reyna and her sister are Circe's two servants/assistants in ''The Sea Of Monsters''.]]
** Gleeson Hedge has a cameo in The Last Olympian as the satyr who wrote Grover from Toronto.
* ElCidPloy: [[spoiler:Silena]] disguises herself as Clarisse to lead the children of Ares into battle in the final book. [[spoiler:She dies just as the real Clarisse shows up.]]
* EldritchAbomination: Maybe the gods, definitely Typhon and the Titans.
* EveryoneCanSeeIt: Between Percy and Annabeth.
* EverybodyHatesHades: [[spoiler:Averted ''and'' invoked by many but also discussed extensively and eventually rectified]] in the books.
* EveryoneIsRelated: Technically, with like one or two exceptions.
** This is sort of subverted in the fifth book where it's explained that gods have no DNA so it's totally not creepy for half-bloods from different god parents [[IncestSubtext to date]], like Silena Beauregard to Charles Beckendorf. They do specify that two demigods from the same parent (a son and daughter of Athena, for example) would never ever consider dating.
* EverythingMakesAMushroom: In the second book, Tyson and Percy, playing with chemicals, make a "miniature mushroom cloud" near the trash can.
** Yes, but Tyson is a Cyclopes (and good at crafting), so for all we know he was playing with depleted uranium or somesuch.
* EverythingsBetterWithRainbows: The ever-handy Iris message. It requires water vapor spray to create a rainbow, so artificial sources are used: in ''The Lightning Thief'', when Percy, Grover and Annabeth are in Denver and contacting Luke at camp, they utilize the spray machine of a self-service car wash. In ''The Sea of Monsters'', the wake kicked up by Percy and Annabeth's lifeboat allows them to create an Iris message intended to go to Chiron, who unfortunately is in the middle of a noisy party, leading to the communication breaking up. Starting in the third book, Percy has a special fountain in his cabin with gold drachmas at the bottom that allow him to communicate with others when necessary.
** They don't like cell phones because monsters can easily trace them.
* ExactlyWhatItSaysOnTheTin: It's Percy Jackson and the Olympians. The titles of the books and chapters do this a lot, too, only [[ItMakesSenseInContext remove any context and most mythical elements,]] making them sound bizarre and hilarious, at the expense of making Percy sound like a madman.
[[/folder]]

[[folder:F-J]]
* FanNickName: R.E.D. for Rachel Elizabeth Dare.
* FailOSuckyname: Gabe ''Ugliano''? Keeping a rebellious streak aside, there's absolutely no way Percy's mom would have sacrificed her maiden name for that surname. Good thing he gets what's coming to him at the end.
* FallenHero: [[spoiler:Luke, other half-bloods, etc.]].
* FatalFamilyPhoto / {{Retirony}}: [[spoiler:Why, Beckendorf? Why did you have to take out her picture?!]]
* FatalFlaw: Played straight with Annabeth, Percy, and [[spoiler:the entire Hades bloodline]]. Played with in that [[spoiler:Athena points out Percy's fatal flaw, but it never ends up being used effectively against him.]]
** [[spoiler:Actually, it does get used against him, quite effectively. Just, never after Athena tells him about it, which may be in part due to Kronos' titanic ego and the fact that they're at war from the point he finds out.]]
*** [[spoiler:While it's not used directly against him per se, we do frequently see Percy get reminded during TLO to stop trying to fight every single battle and save everyone himself, since he'd wear himself into the ground that way. It may not have been mentioned by name, but it's still present.]]
* FightingAShadow: Monsters turn to sand when killed, but eventually return.
** In TheKaneChronicles we finally find out why: they're being banished to the deeper regions of the underworld, and it takes them awhile to claw their way back out.
** And in the newest series, something has happened in the underworld that lets monsters (and the dead) return to earth with relative ease. May, or may not, be related to the events in TheKaneChronicles.
*** Nope, it's because [[spoiler: Gaea opened the gates of Tartarus]].
* FireballEyeballs: Two examples:
** Ares, god of war, has creepy flaming eyes because he's a representation of violence and rage; he normally wears sunglasses to cover them up.
** Hestia also has flames for eyes, but hers are described as much warmer and less creepy; justified, since she's goddess of the hearth, the literal "home fires."
** Similarly, Hyperion has miniature suns for eyeballs.
* FirstGirlWins: Annabeth is the first named girl introduced, unless you count the bully at Yates.
* FirstPersonSmartass
* FixFic: The series has a staggering amount of these, almost all of them either regarding Luke and un-killing him, Thalia and her quitting the hunters in order to be able to be romantically involved, or Rachel Elizabeth Dare being able to date someone even though she too cannot become romantically involved.
* FlirtyStepSiblings: A ''really'' loose example, but Silena, Aphrodite's daughter, and Beckendorf, Hephaestus' son, are technically step-siblings, seeing as their divine parents are married.
** While accurate it should be pointed out that Hephaestus and Aphrodite were an arranged marriage. Most myths state that Zeus had Aphrodite marry Hephaestus so that she would stop causing so many problems with the other male gods and he felt Hephaestus was a person of good character who would be a good husband. While true Hephaestus was also, unfortunately, rather ugly so Aphrodite had NUMEROUS infidelities.
** In other stories Hephaestus knew what he was getting into and had a good sense of humor about it, hence his prank booby traps of epic proportions.
* FlorenceNightingaleEffect: Annabeth in The Lightning Thief (even though it takes a while) and Calypso in The Battle of the Labyrinth
* FluffyTheTerrible: The Mother of all Monsters, the Mighty Echidna, which can put a blowtorch to the St. Louis Arch.
* {{Foil}} / EvilCounterpart:
** Probably accidental, but Hyperion is pretty much this for Hades - one is a god and the other is a titan, DarkIsNotEvil vs LightIsNotGood, and both their names start with "H".
** [[spoiler: Luke]] for Percy.
* FreudianExcuse: Some of the half-bloods blame their parents for not loving them, abandoning them, etc. and use this as their excuse [[spoiler:for joining Kronos's "dark side".]]
* GasLeakCoverup: At the start of ''The Sea of Monsters'', when the Laistrygonians firebomb the gym in their attempt on Percy's life, Percy, Annabeth and Tyson quickly flee because they're certain they're wanted by the police. At the end of the story, when the quest is over, Chiron tells Percy that he convinced the school officials that the bombing was not his fault, by manipulating the Mist to make them think it was just a very badly timed furnace explosion. Percy is still expelled for "ungroovy karma".
* GenreBlindness: Percy has an absolutely terrible track record in terms of recognizing the various mythic monsters and traps he stumbles across, even though most of them are obvious variations on well-known episodes from things like ''Literature/TheOdyssey''. Occassionally, he is GenreSavvy - In ''The Sea of Monsters'' knows Tantalus's background upon first meeting him at Camp Half-Blood. He knows about the Sirens when he and Annabeth encounter them, and the dangers they pose. And in the first book, he knows Procrustes' background.
** [[LampshadeHanging Lampshaded]] once when Percy mentions that they should know they are walking into a trap but after walking for hours, not eating, and craving a bed to sleep on they tend to do stupid things.
** By the time ''Labyrinth'' rolls around, they're more or less GenreSavvy, whereupon the universe actually starts ''changing the rules'' just to throw them off.
* GettingCrapPastTheRadar: Seriously, of all the ways for Mr. D to get Percy's name wrong, his favorite is ''Peter Johnson''? Especially given the reputation of his followers, back in the day...
** The series never outright calls any of the demigods illegitimate, though at one point Hera calls Percy "one of Poseidon's...children," and Percy knows she ''definitely'' implied something else, like "mistakes".
** In the movie, Persephone hates Hades so much she has "visitors" every once in a while. You know, lovers. When she comes across Grover, she says, "I haven't had a satyr... ''visit'' before." Moreover...
*** Also in the movie, Medusa tells Percy "I used to date your daddy." Any Greek mythology student will tell you it was more like a one-night stand. [[DoubleStandardRapeDivineOnMortal A non-consensual one-night stand.]]
** In ''The Titan's Curse'', Percy, Thalia, Grover and Zoe Nightshade arrive at Hoover Dam, causing a hurricane of DAM[[DontExplainTheJoke [N]]] jokes:
--> '''Zo Nightshade''': "Let us find the dam snack bar."
--> '''Grover Underwood''' [smiling]: "The dam snack bar?"
--> '''Zo Nightshade''': "Yes. What is funny?"
--> '''Grover Underwood''' [trying not to laugh] "Nothing, I could use some dam french fries."
** At the meeting with Hyperion, [[spoiler: Thalia]] tells him "That's a load of Minotaur dung." Given that minotaurs are half bull, and "dung" is another word for "shit"...
** The fact that Chiron and Mr. D are running the camp arguably counts, given that Dionysus was eromenos to Chiron in some stories, and apparently learned "the bacchic rites" from him.
** Ganymede is mentioned in the second book, where he says he always buckles up in a recorded safety spiel in the Gray Sisters' Taxicab. His ''special relationship'' with Zeus isn't.
** In the 'Sea of Monsters' movie, Polyphemous laments being forced to eat his sheep. Wait. If they weren't already there for eating, what were they there for? And was he wearing a kilt?
** The 'Honeymoon Special' waterbed in Crusty's Water Bed Palace has dynamic stabilizers to stop wave motion 'wink,wink,nudge,nudge'.
** There's an awful lot of dancing around the conditions for who can or can't be the Oracle in ''TheLastOlympian.'' It's stated that [[spoiler: Maria Castellan]] had major problems with it because she had... [[spoiler: already had children.]] When [[spoiler: Rachel becomes the new Oracle]], they note that she won't be dating anyone anytime soon. If you're familiar with Greek mythology, you know that the Oracle had to be a virgin female.
* GiantEnemyCrab: AttackItsWeakPoint ForMassiveDamage! With some bonus SomedayThisWillComeInHandy.
* {{God}}: Mentioned in ''The Lightning Thief'' during a handwave by Chiron.
--> '''Chiron''': ''God'' capital "G" God is something else entirely. We won't delve into the metaphysical.
* GodlySidestep: Soon after Percy learns about the gods, he asks the obvious question and is informed that the gods are "the lower-case 'g' kind" and they "don't deal in metaphysics." Yes, whether or not He exists is something Olympians don't want to investigate.
** In TheKaneChronicles, the Egyptian gods of the same universe state that they do not demand worship because, while they are primordial forces, they are still created beings. That poses some ''interesting'' questions in light of Chiron's statement on the matter....
* GodsNeedPrayerBadly: Played with, they do not need prayers to exist since the Titans or almost unheard of gods like Khione are still alive and powerful after thousands of years. However, they are tied to their realms of influence and Western Civilization. The weakening of either in an unspecified way can weaken the god. Being remembered and worship can give the gods a reason to live to prevent them from fading. The most direct case is of [[spoiler: Pan. The belief of the Satyrs, Dryads, and other nature spirits are what have kept him from fading away.]]
* GoodIsNotNice: Let's be honest, [[JerkAss the gods are complete assholes]]. Their pettiness and vanity often ends up nearly getting the heroes killed, even when they're trying to save the day. Lampshaded by [[spoiler: Calypso]] when she questions Percy on his loyalty to the gods.
-->[[spoiler:'''Calypso:''']] Tell me Percy. I have no wish to argue with you. But do you support the gods because they are good, or because they are your family?
* GrayEyes: The entire Athena cabin (most notably Annabeth), along with the goddess herself. When Percy notices the gray eyes on the tour guide at Hoover Dam in ''The Titan's Curse'', he realizes it was probably Athena disguised.
* GreenAesop: Various sea and river creatures get uppity around water pollution, and [[spoiler: the quest for Pan eventually turns out to be all about the current state of the environment; this one is extremely well-done, though]].
* HalfHumanHybrid: The Minotaur is just one of the first examples. There are numerous others that number so many we would be tracked down if their names were posted here.
* HawaiianShirtedTourist: Mentioned word for word in ''The Lightning Thief''.
* HeelFaceRevolvingDoor: [[spoiler: Daedalus]] and [[spoiler: Prometheus]].
* {{Hellhound}}: Several in the series, including the quite nicely oversized hellhound named [[FluffyTheTerrible Mrs. O'Leary]].
* TheHerald: Grover. Chiron.
* TheHeroDies: Played straight, and yet not, in that [[spoiler:the hero was not who we all thought he was.]])
* HeroicBastard: All of the half-bloods, of course, with the possible exception of Athena's children (it depends on whether you can consider children born from thoughts bastards or not). Despite this, the B-word is never outright mentioned, although Hera alludes to it at one point.
* HeroicLineage: Again, of course.
* HeroicSacrifice: [[spoiler:Beckendorf, Luke, and Bianca]]. [[spoiler: Silena]] counts too, with her [[spoiler: ElCidPloy]].
** Um, hello! [[spoiler: Zoe Nightshade? She jumped in front of one of the most powerful Titans in the world to save Artemis.]]
* TheHerosBirthday: Percy's 16th birthday
* TheHerosJourney: Every quest Percy takes
* HiddenInPlainSight: Labyrinth entrances. There is one inside Alcatraz. Also, you can find one on the North Shore of Long Island at some ordinary strawberry farm, and at the Times Square Marriott.
** If you want to go to Mount Olympus, go to the Empire State Building and get a special card for access to the 600th floor.
** The Underworld entrance - DOA Recording Studios in the book, and underneath the Hollywood Sign in the film.
** You should never venture near Mount Tamalpais if you are visiting San Francisco. Although in reality there is a weather station up there, there are a lot of very supernatural things going on around there.
* HistoricalInJoke: Just think about it.
** It's obvious Poseidon's wrath caused Hurricane Katrina.
** Hades causes an earthquake in Los Angeles, which implies that he probably also caused the Northridge earthquake of 1994, the San Francisco earthquake of 1906 and the Loma Prieta quake of 1989.
** Edward Teach, Blackbeard, was a son of Ares. And he was ''not'' killed in battle with Virginia soldiers. Rather, the soldiers captured him and handed him over to Circe, who transformed him and his crew into guinea pigs.
* HonorBeforeReason: Percy doesn't want to kill a [[SarcasmMode poor pitiful]] Polyphemus, given that he's bonding with Tyson as best he can. So Polyphemus actually lives, and [[ItMakesSenseInContext thinks he's sunk Nobody]].
* HopeSpot: ''Literally'' in ''The Last Olympian'' when Percy gives [[spoiler:Pandora's Box]] to Hestia, and the warmth of her hearth fires inspires him to keep fighting. And despite more bad developments which happen after this, [[SubvertedTrope it isn't dashed]] since they do win.
* HumansAreTheRealMonsters: Grover and the other satyrs believe this, given their belief that humans mistreated the earth [[spoiler:following the death of Pan]]. Grover [[spoiler:goes so far as to play a version of Deer Hunter...where the ''deer'' shoot humans, and he ''laughs gleefully'' while they do so]]. Even Hades, ''the Lord of the freakin' Dead'', thinks this, as the events of the 20th-century led to overcrowding in the Underworld [[spoiler:even though those events were caused by squabbling demigods, not humans]]. Percy also shows shades of this at first, given that he's dealt with nothing but bullies and [[spoiler:his abusive step-father]] for his whole life. He grows out of this over the course of the first book however, growing to care for the safety of an innocent family and seeing [[spoiler:his step-father]] as one of the worst examples of humanity rather than being par for the course.
* [[HumansAreMorons We Are Morons]]: Given the setting, the vast majority of humans come off as this, incapable of accomplishing anything greater than desk-jockeying without divine parentage.
* HumansAreSpecial: Most aren't particularly notable, but a few of us have traits (i.e., a high level of creativity, stunning looks, above-average intelligence) that make us desirable to the gods. YMMV on if that's a good thing, especially given Zeus' way of...erm, ''treating'' those he takes a shine to.
* HumanMomNonhumanDad: Percy, Clarisse, Thalia, and Luke fit under this category, being the children of male gods. Reverse with Silena Beauregard and Annabeth.
* HybridPower: Demigods are often chosen by the gods to do their work because being half-god and half-mortal, they straddle both worlds and can go places and do things that either mortals or gods cannot.
* ICanStillFight: [[spoiler:Annabeth and Pollux in ''The Last Olympian'']].
* ICannotSelfTerminate: [[spoiler: Luke needs to destroy himself to defeat Kronos, but can't do it without Percy giving him Annabeth's knife.]]
* IconicSequelCharacter: Thalia Grace does not appear until the very end of ''The Sea of Monsters'' and doesn't do anything until ''The Titan's Curse'', but became extremely popular with the fanbase. Her connection with one of the primary characters of the Sequel Series ''Literature/TheHeroesOfOlympus'' solidified her importance.
** Ditto Nico di Angelo, who first appears in ''The Titan's Curse'' and becomes a major player in ''The Battle of the Labyrinth'' and ''The Last Olympian.'' And like Thalia, he has a connection to one of the main characters of Heroes of Olympus.
* IdiotHero: Percy is not exactly the sharpest blade on the weapons rack.
* IFoundYouLikeThis: Percy collapses after fighting the Minotaur outside of Camp Half-Blood. After winning the fight, he awakens inside the camp being tended to by Annabeth Chase.
** Percy's arrival at Calypso's island in ''Battle of the Labyrinth''. He passes out while being catapulted out of Mount St. Helens, and when he wakes up, Calypso is treating him.
* InWhichATropeIsDescribed: Every chapter likes to explain exactly what happens in said chapter, usually in sarcastic and witty ways: "I Accidentally Vaporize My Pre-Algebra Teacher", "A God Buys Us Cheeseburgers", "[[ItMakesSenseInContext Grover Buys a Wedding Dress]]", "[[CueTheFlyingPigs Pigs Fly]]"...
* IGaveMyWord: An oath on the River Styx is magically binding. Unless you are a god.
** Gods are supposed to be bound by it as well and if they break their word exiled from Olympus for a decade without receiving any divine food. Of course, Zeus being the god in charge of enforcing oaths and not exactly a great role model he decided to not enforce the consequences on himself and the same with Poseidon.
** In fact, a promise is not binding unless sworn on the River Styx, [[ChekhovsGun something taken advantage of several times in the series]]. Such as in ''Battle of the Labyrinth'' when Percy offers to clean Geryon's stables. He fails to take the oath.
** But, according to the books, Zeus is punished through Thalia, who [[spoiler: is turned into a tree.]] Arguably, Poseidon's punishment may be due to Percy being the child of the prophecy.
* IKnowYouAreInThereSomewhereFight: Annabeth wearing her invisibility cap and distracting Polyphemus by making him think Nobody has returned (Odysessus)
* [[INeedToGoIronMyDog I Need to Go Polish My Hippocampi]]: ''Battle of the Labyrinth'' gives us this exit line from Tyson:
-->'''Tyson:''' I need to go... um... polish my fish ponies.
* InferredSurvival: Even after the climax, it's revealed that [[spoiler:Kronos is still out there somewhere, as he is immortal and cannot die.]] It is said that [[spoiler: Kronos might be scattered so thin across the world that he might not be able to form a consciousness again]], but what would be the fun in that coming true?
* InnocentlyInsensitive: Perdix, it is ''not'' a good idea to ask your uncle Daedalus if his son died flying because the wings he made him failed.
* InterspeciesRomance: Where would a series based on {{Greek mythology}} be without it?
* IslandOfMystery: The Island of Ogygia.
* ItWasAGift: Good gifts, cursed gifts, it's all good.
* JediMindTrick: Or as we should call it here, Manipulating the Mist. Thalia uses it in ''The Titan's Curse'' to trick Dr. Thorn and another teacher into thinking that she, Percy and Annabeth are Westover students and not visitors on a rescue mission.
* {{Jerkass}}: Gabe Ugliano. Good thing [[spoiler:it's implied Sally turned him into a statue with Medusa's head]]. He deserved the comeuppance.
** Annabeth, Thalia and Clarisse have shades of this in different books.
* JerkJock: The Ares Cabin in general, and Clarisse in particular.
* JustTrainWrong: There are a couple of glaring instances when it comes to railroads being used in the stories.
** For instance, in ''The Lightning Thief'', Percy, Annabeth and Grover take an Amtrak train from New Jersey to Denver, Colorado - a one-seat ride that also goes through St. Louis (for the Echidna encounter in the Arch). There are several things that are extremely inaccurate with their journey:
*** A one seat ride from New Jersey to Denver via St. Louis is impossible. There are no coast-to-coast intercity trains in the United States (the ''Sunset Limited'' used to run from Orlando to Los Angeles until August 2005 when Hurricane Katrina truncated the route to New Orleans). Any intercity trains out of Penn Station only go as far as Chicago, requiring a change of trains there. Also, although Amtrak has trains to Denver and St. Louis, completely different trains reach these cities from Chicago - the ''Texas Eagle'' for St. Louis and the ''California Zephyr'' for Denver.
** In ''The Titan's Curse'', the heroes board an autorack freight train in Washington DC and wake up the next morning in Cloudcroft, New Mexico. It should be noted that the nearest railroad to Cloudcroft is in Alamogordo. Furthermore, it's impossible to travel the distance overnight, although it's also possible Apollo had something to do with speed up the pace of the journey.
[[/folder]]

[[folder:K-O]]
* KidHero: Just about every single half-blood in this book. Just about.
* KilledOffForReal: Everyone that dies in the series. Luke not dying even though Percy thought he did in ''Titan's Curse'' doesn't really count because Annabeth told him about thirty seconds later that Luke wasn't dead. The only aversion to this is Tyson. Everyone else thinks that Percy dies, too, but since the story is from his perspective so we know otherwise, it doesn't count.
* KissingCousins: Percy's father, Poseidon, is Annabeth's great uncle, making the two of them second cousins. However, [[IncestIsRelative considering the giant amount of incest]] that is Greek mythology, this doesn't come up at all.
** ''All'' the incest in Greek mythology is eventually explained in-series by the idea that the gods have no DNA and therefore cannot inbreed. Demigods at Camp Half-Blood feel free to date any fellow demigod who does not share a divine parent--in other words, two Athena kids (half-siblings) would not go out, but [[OfficialCouple an Athena kid and a Poseidon kid]] might, regardless of their technical relationship.
* TheLadette: Clarisse. She is Ares' daughter, after all.
* LandmarkingTheHiddenBase: Mount Olympus is reachable via a special elevator to the 600th floor of the Empire State Building.
** Alcatraz contains a Labyrinth entrance.
** The Hollywood Sign is the Underworld entrance for the film of the first book.
* LamarckWasRight: The big three weren't born as rulers of their domains, they divided the world up after defeating their father. In addition, gods apparently don't have DNA. As such the heroes inheriting some of their parent's powers, especially when it comes to children of the Big Three, is an example of this.
** Does it count as LamarckWasRight if it's explicitly a divine legancy instead of being biological?
* LeeroyJenkins: Percy.
* [[LetsGetDangerous Let's Get Dangerous]]: In ''The Last Olympian'', it's calm, quiet [[spoiler:Sally Jackson and Paul Blofis. Who thought that two humans, one of whom can't even see through the Mist, could kick so much monster butt?]]
** Mr. Chase gets a moment when he manages to kill a large number of the Titan's army using an antique plane he outfitted with a automatic gun that fires [[ThunderboltIron Celestial Bronze]] bullets. He has one of the highest kill counts in the series.
* LibationForTheDead: Nico must offer food and drink to consult spirits. One chapter in ''Battle of the Labyrinth'' is even titled "Nico Buys Happy Meals For The Dead." Typically he uses french fries and coke.
** Minos, his TreacherousAdvisor, complains that it's traditional to use animal blood for necromancy. Nico tells him to shut up.
* LIsForDyslexia: Half-bloods are all dyslexic, since their brains are "hard-wired" to read Ancient Greek instead of English. As a result, reading even regular signage is difficult unless it's in very large font.
* LikeABadassOutOfHell: In ''The Last Olympian'' after Percy [[spoiler: gets the Achilles curse in the Underworld, he faces off againgst Hades' army and ''wins'']].
** It's supposed to be the ultimate prison and it's constantly said that no one, even the greatest heroes could escape. Percy does it when he's ''twelve''.
** Nico, being the son of [[spoiler: Hades]] naturally screws this trope to [[IncrediblyLamePun hell]].
* LivingLabyrinth: Daedalus's Labyrinth grows over time. It's grown enough to apparently also develop Roman elements.
* LoadBearingHero: Percy and Annabeth both pull this one, except they're holding up the ''sky'', technically making them load-bearing heroes for the entire planet.
--> '''[[PhysicalGod Artemis]] (preparing to launch Atlas back under the sky):''' ''Get ready!''
--> '''Percy (holding up the sky)''': ''Aaaaaargh - ow''
* LockedIntoStrangeness: Percy and Annabeth get matching gray streaks in their hair after [[spoiler:holding up the weight of the sky]] in ''The Titan's Curse''.
* LockedOutOfTheLoop: Percy, for much of the series. Sally and Paul, too. And of course poor Frederick Chase out there in San Francisco.
* LotusEaterMachine: The Lotus Hotel & Casino, named after the TropeNamer. Time speeds up significantly. Two weeks in that hotel is 28 years in the real world, and one hour is the equivalent of five days.
* LoveableRogue: Hermes, as in mythology--and by extension, most of his demigod children. [[spoiler:Luke is a subversion]].
* MadOracle: [[spoiler:May Castellan.]]
* MadeOfIron: [[spoiler:Luke and Percy.]] And Achilles and the Nemean Lion.
* MagicCompass: In ''The Demigod Files'' short story "The Sword of Hades", Percy, Thalia and Nico are given a flower by Persephone that will point the direction the thief who stole the titular sword is in. It loses petals the closer the thief gets to escaping.
* MagicalNegro: Averted quite nicely:
** The [[OurCentaursAreDifferent centaur]] Chiron originally appears as a [[SuperWheelChair wheelchair-bound]] Latin teacher. But early in the series, we learn that his wheelchair is merely a {{hammerspace}} device to conceal his horse legs. Although he's Percy's mentor, he doesn't merely serve and glorify Percy--he's plenty capable of his own [[{{badass}} badassery]].
** Tyson originally appears to be mentally challenged [[TwoferTokenMinority AND]] homeless. Turns out he's a Cyclops, so his intelligence is naturally lower than a human's. Like Chiron, he doesn't merely serve the humans in the series, and is a complete {{badass}}. He always keeps his CloudCuckooLander and [[TheDitz ditzy]] tendencies, though.
** Played straight when Apollo briefly appears as a homeless man.
* [[AppleOfDiscord Mango Of Discord]]: Hilariously used by the Stoll brothers to pull a prank off the Aphrodite cabin in the Demigod Files.
* MarkedToDie: [[spoiler:Zoe]] realized from the beginning who the one meant to die by a parent's hand was.
* TheMarvelousDeer: In the ''The Demigod Files'' short story "The Sword of Hades", Thalia is led to meet Percy and Nico by the Golden Hind, which is, in fact, ''literally'' gold.
* MasqueradingAsTheUnseen: Annabeth distracts Polythemus from her friends by donning her [[InvisibilityCloak invisibility hat]] saying she's Nobody, an alias Odysseus used to outsmart the cyclops in ancient times. It works, but then she gets caught, so Percy hides from view and does the same thing.
* MatterOfLifeAndDeath: [[spoiler: Words spoken by Rachel to convince her father that Percy is in danger.]]
* MeaningfulName: Most of the more minor half-bloods have names which reflect their divine parent. Hephaestus has a kid whose last name is Mason, Apollo has sons whose last names are Yew and Fletcher...
** Riordan didn't bother with some of the minor half-bloods, but the worst offender has to be Demeter's daughter. Demeter is the goddess of grain, fertility, and harvesting. Her daughter is Katie ''Gardner''.) Grover, who has a big fixation on nature (he's a satyr, it's his job), has 'grove' in his name, along with his surname, ''Underwood''.
** Also, in the case of Silena Beauregard (daughter of Aphrodite) whose surname means ''beautiful gaze'' in French.
** Don't forget Conner and Travis ''Stoll''. The sons of Hermes, god of ''thieves''. Percy even points this one out, it's so obvious. It might be interesting to point out that Conner and Travis Stoll are real brothers who at one point were in Riordan's class. Charles Beckendorf, albeit with a different appearence, was also a student.
** A rather tragic example: "Zoe" means "Life". And her last name is "Nightshade." Nightshade is another name for a family of of poisonous plants. [[spoiler: Just how did Zoe die again? Oh yeah, POISON was a part of it!]]
** Also Rachel Elizabeth Dare, in a StevenUlyssesPerhero-ish way. And ''boy'', does Rick Riordan feel proud of ''that'' particular idea. Her initals are RED, and she has red hair. Probably coincidence.
** People might not necessarily remember Mrs. O'Leary, but they sure remember the lantern [[http://en.wikipedia.org/wiki/Great_Chicago_Fire her cow]] kicked over.
** ''Perseus'' Jackson, people!
* MegaNeko: The Nemean Lion
* MonumentalBattle: The Gateway Arch in the first book.
** MonumentalDamage: Again, the Gateway Arch. The Chimera burns a hole in it.
-->"Great, we just blowtorched a national monument."
** Also, to the Air & Space Museum in ''The Titan's Curse'' due to a Nemean Lion attack (which will certainly put the Secret Service and FBI on high alert), and a lot of trouble at Alcatraz in the fourth (with Kampe and Briares).
** Not to mention damage done in the last book.
* MoreHeroThanThou: Inverted by ''The Titan's Curse'' [[spoiler:Percy practically pleads for Artemis to let him hold up the sky for her because she could fight better than he could.]]
** It's played with in that scene. Percy had no problem with [[spoiler:going head-to-head with Atlas.]] It wasn't until [[spoiler:Ares's curse kicked in and sapped Percy's sword skills]] that he even tries to take the sky.
* MrFanservice
** Ten, if you count the fact that in LO, there's the line "Six Aphrodite girls kissed me on the cheek in excitement."
* AMythologyIsTrue
* NamedWeapons: Anaklusmos/Riptide (Percy's pen-sword) and Backbiter (Luke's sword).
** Subverted hysterically with Clarisse's "Maimer" (electric spear), which all the campers mockingly nickname "Lamer".
* NarrativeProfanityFilter: Both English and Ancient Greek.
* NatureSpirit: The nymphs and dryads.
* NeurodiversityIsSupernatural: Demigodhood causes dyslexia and ADHD.
* NeverFoundTheBody: More like [[spoiler:Never Found the Disembodied Evil Titan Soul...]]
** A truer example: [[spoiler:Bianca]]'s body was never recovered, nor is [[spoiler:Michael Yew]]'s.
*** Then again, it's not like you ''need'' to find the bodies when [[spoiler:Hades or his son can tell you whether or not they really died.]]
* NiceJobBreakingItHerod: Kind of. [[spoiler: By killing Maria di Angelo in an attempt to kill Nico and Bianca, Zeus just gave Nico a reason to hate and want to destroy the gods, which is what Zeus was trying to prevent. Luckily, Nico didn't act on it. But Hades, in anger at his mistress being killed, cursed the Oracle so she goes all crazy. Luke's mom volunteers to be the Oracle but gets driven mad. Luke feels left alone and resents his parents as a result]]
* NiceToTheWaiter: [[spoiler: Hestia, in the form of a young girl,]] says that almost no one (including Percy) ever stops to speak with her. Nico di Angelo is one of the exceptions.
* NoEyeInMagic: Percy, Grover and Annabeth encounter the actual Medusa from Greek Myth. Percy sees her through a glass gazing ball, so he doesn't get {{Petrified}}. In TheFilmOfTheBook, he uses an iPod Touch to glimpse ahead before turning corners for the same reason.
* NoodleImplements: Grover offers to show the Hunters of Artemis to their cabins in ''The Titan's Curse''. When he shows up again while Percy and Thalia are about to break bad news to Chiron, he shows up again, grinning, with a black eye and red lines that clearly look like a slap mark. It doesn't take much to figure what happened.
* NoodleIncident: One of the key events of a year at Camp Half-Blood prior to the series involves a centaur in a prom dress; Annabeth remarks, "Now that was a weird summer."
** In ''The Last Olympian'', when Percy arrives at Camp Half-Blood:
-->"Our beach is on the North Shore of Long Island, and it's enchanted so most people can't even see it. People don't just ''appear'' on the beach unless they're demigods, or gods, or [[ArsonMurderAndJaywalking really, really lost pizza delivery guys]]. (It's happened-- but that's another story)."
** This line from ''The Sword of Hades''
--->'''Nico (to Persephone):''' Family spat? You turned me into a dandelion!
** This is sometimes used in an individual book to refer to events that happened in previous ones without giving the details away. For example, from ''Battle Of The Labyrinth'', in a conversation between Percy and his mom;
---> "I ''told'' them you were all right," my mom said, but she sounded like the weight of the sky had just been lifted off her shoulders - and believe me, I know firsthand how that feels.
** In ''The Titan's Curse'', it's said that the Hunters didn't have a very cordial encounter the last time they were at Camp Half-Blood. Including the fact that they burned down a few cabins.
* NoMatterHowMuchIBeg: In Book 2, Annabeth wants to hear the Sirens, but doesn't want to get killed. She then asks Percy to tie her up and never let her go, so Percy fills his ears with wax so he can't hear the Sirens ''and'' her pleas. [[spoiler: Unfortunately, she still has her knife, so she eventually escapes. Percy comes after her and manages to grab her before she could drown. Also, he realizes that she can't hear them underwater, so he creates a giant air bubble for them to stay in until the song's over.]]
** Fortunately, Percy is savvy enough to know how to avoid the danger.
* NoOneCouldSurviveThat: [[spoiler: Luke's 50-foot fall in ''Titan's Curse'', which, of course he did survive.]]
* NormallyIWouldBeDeadNow: Played so straight ''it hurts.'' But for Percy, anything with water is justified because he's the son of the sea god.
* NotADate: Percy insists his planned afternoon with Annabeth at the start of ''Battle of the Labyrinth'' is not a date, though his mom thinks otherwise.
* TheNothingAfterDeath: The Asphodel Fields of Greek mythology, the most widely populated part of the Underworld.
-->'''Grover:''' Imagine standing in a wheat field in Kansas. Forever."
* OfficialCouple: By the end of the series, there's [[spoiler:Percy and Annabeth, Clarisse and Chris, and Grover and Juniper]], among others.
* OffingTheOffspring: In book three: ''one shall fall by a parent's hand.'' (It was [[spoiler:Zoe Nightshade]].)
* OhMyGods: Practically the trope namer.
* OneWingedAngel: [[SubvertedTrope Subverted]] [[spoiler: Kronos is defeated before he can show his true form and make his enemies despair.]]
** Ares does pull one at the end of the first book,[[spoiler: but only after already losing the fight from getting stabbed in the heel. He was about to go kill Percy for sure when Kronos evidently changed his mind and he settled for cursing Percy and going somewhere to heal instead, turning into his full divine form to warp somewhere else. [[BrownNote But looking at it would have killed Percy]].]]
* OutgrownSuchSillySuperstitions: Percy attempts to tell this to Dionysus. He is promptly set straight.
** Dionysus explains how people from all times laugh at the lack of knowledge the past had, and how in the future people would be laughing at people of Percy's time for what they didn't know.
* OverlyLongGag: In ''The Titan's Curse''- the entire DAM[[{{DontExplainTheJoke}} (N)]] sequence.
[[/folder]]

[[folder:P-T]]
* PaperThinDisguise: [[spoiler: Silena leading the Ares cabin to battle in the last book. Even [[{{LampshadeHanging}} Lampshaded]] by Clarisse.]]
--> "Seriously, not one of you noticed?!"
** FridgeBrilliance: This is why you never underestimate [[spoiler:Aphrodite. Her daughter could have easily influenced the Ares cabin's [[BloodKnight love for war]] and loyalty to their campmates.]]
** It is also implied that by that point [[spoiler: Clarisse's stubbornness was the only thing keeping the Ares cabin from entering the war. So her cabin-mates were happy to make any excuse to come to the battlefield. Saying "we fell for the disguise" was as convenient an excuse as any.]]
* ParentalAbandonment: Every half-blood is abandoned by their immortal parents and gets occasional visits ''if they're lucky.'' Lots of half-bloods never even learn who their divine parent is.
** Also averted by the ''mortal'' parents like Sally Jackson and later Paul Blofis, and Annabeth's parents.
*** Not so averted by [[spoiler:Luke's mom May]]. She's there, but she ain't ''there''. [[spoiler:Thalia]]'s mortal mom doesn't sound like she would have won any parenting awards either, [[spoiler:not even when she was alive]].
* ParentalFavoritism: Greek gods are genetically guilty of this.
** Poseidon openly admits that [[spoiler: Percy is his favorite son. Which is a CrowningMomentOfHeartwarming of its own. That, itself, becomes something of a FunnyAneurysmMoment when Triton appears in the fifth book and is [[TheUnfavorite clearly jealous of Percy]].]]
* PatchworkKids: You'd be amazed by how many fanfics feature Percy/Annabeth crosses that have one gray eye and one green eye, blond hair with black streaks, green eyes with flecks of gray, etc.
* PerkyGoth: Nico and Thaila.
* PetTheDog: Dionysus, who's quite a grouch and always seems happy to put Percy and his friends down, helps out Grover in ''The Battle of the Labyrinth'', supporting him when he [[spoiler: announced that the god Pan was dead]]. He also showed genuine grief for [[spoiler: his son Castor]] when he died, and helped cure half-blood Chris Rodriguez who had previously gone insane. It's also subtly implied that he's a hell of a lot more pleasant when he's around his wife, who he genuinely loves (despite the standard Greek god one night stands applying).
** [[BloodKnight Ares]] gets one as well, when he gives a SoProudOfYou line to his daughter Clarisse.
** Which is made sweeter and/or kinda sad when it's been made pretty clear he's literally abusive and Clarisse was still worried she'd get hit or blamed somehow.
* PhysicalGod: Well, yeah.
* ThePlan: Kronos pulls off quite a few.
* PoweredByAForsakenChild: Percy speculates that someone has been killed to make Luke's sword.
* ThePowerOfFriendship: In ''The Last Olympian'', why the Ares's cabin campers followed [[spoiler:Silena; they didn't guess it wasn't Clarisse because they wanted to go fight next to their friends.]]
* PowerTrio: Typical for anything Greek, since three is a sacred number. So many examples, but here's just a few:
** Obviously, the Big Three: Zeus, Poseidon, and Hades.
** Then there's their kids, Thalia, Percy, and [[spoiler:Nico]] ([[spoiler:they start off numbering four, but Bianca gets offed fairly quickly and before her parentage is even known]]).
** Thalia, Luke, and Annabeth.
** It's a camp rule that any hero who sets out on a quest is allowed to take two and ''only'' two companions, specifically ''because'' three is a good number. The rule is broken twice, the first time with disastrous consequences.
*** It was actually broken only once--in ''The Titan's Curse'', the first time more than three people travel on a quest was due to the prophecy, but the prophecy warns that "one shall be lost in the land without rain" (Bianca Di Angelo, killed by a defective Talos statue in southwest Arizona) and "another shall perish by a parent's hand" (Zoe Nightshade). Camp rules don't apply when the Oracle is the one that is doing the talking.
** The most obvious one: Percy, Annabeth, and Grover. They're the three main ones for most of the quests and are ''really'' close.
* ProductPlacement: A freakish amount in the first book. Burger King! Coca-Cola! Oreos Double Stuf cookies! Even Lunchables! And that just scratches the surface. But it's possible that Riordan didn't want to have to come up with too many fictional brand names because that would be too difficult. Exceptions, however, come in the form of the Monster Donut chain.
** In ''Battle of the Labyrinth'', Nico uses McDonalds Happy Meals to summon the dead spirits in one scene. [[BlackComedy One ghost complains when he isn't allowed to get the toy!]]
* PropheciesAreAlwaysRight: Every prophecy comes true.
* ProphecyTwist: One in every book. In fact, it wouldn't be Percy Jackson without 'em.
* PsychicDreamsForEveryone: Well, almost everyone. How nifty.
** It's even {{Lampshaded}}. During a war, Percy and another half-blood have an exchange about how they need to sleep but ''really'' don't want to. Percy, in narration, explains that demigods' dreams suck, since they're frequently visions and prophecies and other psychic junk which isn't fun at all, and the more tense things are the worse the dreams are. For a while, Percy even had Kronos showing up in his dreams to taunt him (and Kronos is good at it, too.)
* {{Pun}}: Percy is able to sneak these by people who are more familiar with Greek mythology. A shining example from the fourth book... "Red cattle. The cattle of the sun. They're sacred to Apollo." "Holy cows?" "Exactly. But what are they doing--"
* PunnyName: Cassandra Dare (as opposed to CassandraTruth)
* PutOnABus: [[spoiler:Thalia, the Hunters, Chris. The implication is that they're off having adventures, just like Percy and his friends.]]
* ReallySevenHundredYearsOld: All the gods, plus several demi-gods.
* RecycledInSpace: Although [[TropesAreNotBad it's done well]] in this case. Many of the plots or subplots are the major arcs of well-known Greek myths. ''The Sea of Monsters'' is Jason and the Argonauts and the Odyssey stuck together. [[spoiler:Silena's fight against the monster in the final book and Clarisse's subsequent beatdown of the monster that killed her is Patroclus stealing Achilles' armor and Achilles' fight with Hector, complete with dragging the corpse around behind her chariot.]] Riordan was quite clever in working the myths into his books.
** This is Justified in the fifth book, when Prometheus says that patterns repeat themselves in the world.
** This also comes up in TheKaneChronicles, where the reason gods want mortal hosts is that they can change those patterns.
** The series as a whole could be considered Literature/HarryPotter WITH Greek Mythology.
* RedemptionEqualsDeath: [[spoiler:Daedalus in ''The Battle of the Labyrinth.'' Silena, Ethan, and Luke in ''The Last Olympian.'']]
* ReformedButRejected: [[spoiler:Nico di Angelo, until the very end.]]
* RefusalOfTheCall: Played straight and played with in ''The Titan's Curse.
** In the first case, it's played straight when [[spoiler:Thalia joins The Hunters to avoid turning 16. Thus, meaning that The Great Prophecy can't mean her.]]
** It's played with with [[spoiler:Bianca. Who was completely in the running for being TheChosenOne, except she decided to join The Hunters long before anyone knew that she was a daughter of Hades.]]
* RefusingParadise: [[spoiler: Percy Jackson refuses the offer to become lieutenant to his father, Poseidon, and gain eternal immortality. He refuses it on the grounds that he's about to enter high school and he doesn't want to lose the possibilities his regular life gives him, but it's heavily implied it's so he can stay with Annabeth.]]
* RememberTheNewGuy: The [[WeirdnessCensor Mist]] can be manipulated to create FakeMemories of a person. For example, after Mrs. Dodds (Percy's teacher and a servant of Hades) attacks Percy and is killed, a new teacher named Mrs. Kerr mysteriously appears to take her place, and nobody but Percy remembers that Mrs. Kerr hadn't always been their teacher.
* RhymesOnADime: "Curse me, eh, I'll make you pay/ I don't want to rhyme all day!"
* RiddlingSphinx: When Percy, Annabeth, Grover and Tyson meet a sphinx in the Labyrinth in ''Battle of the Labyrinth'', it tries to administer a multiple-choice standardized test, with mundane trivia questions (in the style of a game show with regards to her tone of voice, and the use of recorded applause from hidden speakers). Annabeth, who was expecting a riddle that would test her cleverness, is not amused.
** Rick Riordan lives in San Antonio, Texas, and wrote the scene as a jab at the TAKS, the standardized test of Texas's grade schools at the time of publishing. The Sphinx's instructions being word for word the script teachers have to recite down to the instructions given on properly bubbling in the answers.
* RomanticFalseLead: [[spoiler:Luke is one for Annabeth. Rachel is a False Lead for Percy.]]
* RunningGag: Characters cursing in Ancient Greek, or, "I said something really intelligent like..."
* SchoolSavedMyLife: Chiron points this out about Percy's Greek History before Percy knows anything. Then it is taken to the extreme when he goes to Camp Half Blood. Played straight for almost everyone.
* ScienceIsWrong: Among other things, the seasons are caused by Persephone moving between the Underworld and Olympus, not the Earth's tilt, and global warming is simply Zeus being ornery. However, it's implied that there might be a combination of both, as the moon and sun clearly exist as physical forms, not controlled by Apollo and Artemis.
* TheScottishTrope: Saying "The Furies" or the names of any god or titan causes thunder to rumble (and apparently, [[WordPower gives power to that god/titan]]). Even when there aren't any rain clouds around. At least once or twice in book 1, Grover is about to refer to the Furies as such, but changes midway through saying it to say "Kindly Ones".
* SelfFulfillingProphecy: [[spoiler:Zeus killed Maria di Angelo in order to prevent Big Three children so that Kronos won't try to take over the universe. Hades, in anger at his mistress being killed, cursed the Oracle so she goes all crazy. Luke's mom volunteers to be the Oracle but gets driven mad. Luke feels left alone and resents his parents as a result. Kronos uses this as an opportunity to manipulate Luke into helping him rise. ''Zeus just caused the prophecy to take place in the worst way possible.'']]
** That is the beauty of it. You can't fight fate: the only way to not fulfill a prophecy is to simply not hear it, because once you do, it will happen.
* SemiDivine: Most of the main characters are demigods.
* SequelHook: The prophecy at the end of ''The Last Olympian''.
* SequelSeries: [[TheHeroesOfOlympus The Heroes of Olympus]]
* ShadowWalker: Nico di Angelo is able to "shadow travel" because he's the son of Hades, he claims that every shadow is one and the same, however he can only do it a couple of times per day preferible at night, also it drains him a lot to the point the first time he used it he passed out for a whole week
** Also, Mrs. O'Leary, like all hellhounds, can do this.
* ShipperOnDeck: Aphrodite is a big Percy/Annabeth shipper. Though (understandably) she thinks life is a soap opera ({{Lampshaded}} by her beau, Ares), and so assures Percy that she won't let things be easy for them ([[spoiler:unintentionally lampshaded by Annabeth herself at the end]]), with plenty of {{Wangst}}, [[WillTheyOrWontThey indecision]], etc.
* ShipTease: Thalia/Luke. Two best friends who ran away together for roughly three years. Then Luke [[spoiler:joining the Titans because one of his reasons was because of her death.]] ''The Titan's Curse'' also has a lot of moments where you find out that Thalia once considered [[spoiler: joining the Hunters, but did not want to because she would be away from Luke.]] Then there was their final battle in ''The Titan's Curse'' which implied quite a bit.
** Also, Annabeth/Luke. It started out as a crush on Annabeth's side. Annabeth also defends Luke many, many times in the books. In ''The Last Olympian'', Thalia said that she [Annabeth] always saw Luke as her hero.
** And there are ''so'' many Percy/Annabeth moments that it could make a shipper faint.
* ShipSinking: [[spoiler: Thalia/Luke by the end of ''The Titan's Curse''.]] Good luck, shippers.
** Though fans still ship them. There is the whole [[spoiler: breaking her vow]] thing there. [[spoiler: And Thalia seems to generally care for him, still. It did seem like Luke was shunning Thalia by the fifth book when he went to Annabeth's house and said that Thalia would never leave the Hunters.]] But by ''The Last Olympian'', it implies that Thalia enjoys [[spoiler: being part of the Hunters. She's the freakin' lieutenant.]]
* ShoutOut: Too many shout outs to GreekMythology to list. This is in part because author Rick Riordan is also a Greek researcher.
** The Empire State Building's guard with the special 600th floor card for Mount Olympus apparently keeps up with Young Adult Literature fads.
*** In ''The Last Olympian'', he is seen reading [[Literature/{{Twilight}} a big black book with a flower on the cover]].
*** In ''The Lightning Thief'', he is reading [[Literature/HarryPotter a huge book with a picture of a wizard on the front.]] One guess who this "wizard" might be.
** Nico di Angelo has a Mythomagic card game, a reference to card games such as ''Magic: The Gathering''. This is now Hilarious In Hindsight; Magic's newest set is based on Greek mythology.
** Nico references [[{{SpiderMan}} Spidey]] in ''The Last Olympian'' after taking Percy by shadow-travel on Mrs. O'Leary: [[{{ComesGreatResponsibility}} "With great power...]][[{{SubvertedTrope}} comes great need to take a nap."]]
** The books also have a character called Will. Will's namesake is a shout out to a certain [[Creator/WilliamShakespeare play write and poet]] who, in universe, was said to also be a son of Apollo.
* ShownTheirWork: If a monster is named in the books, it exists in Greek Mythology exactly like it does in the books. References to the Illiad and The Odyssey abound. if there's a place described that exists in real life you can recognize it from descriptions. Even epithets are alluded to (grey eyed Athena for instance). Riordan has clearly read the Theogony, the Illiad, The Odyssey, and a number of other minor books including Ovid's Metamorphoses. It shows up with bits like Apollo mentioning he really hates it when girls get turned into trees, or a thermos that perfectly mimics Odysseus' bag of winds.
** Rick Riordan had been an editor of mythology books in the past - and it shows. He even brings other mentions into its sequel series, bringing in "Roman aspects".
* SnicketWarningLabel: Percy warns you that you should ''immediately'' put the book down if any of the descriptions of a demigod sound familiar to you, because if you figure it out, monsters will find you and probably kill you.
* SoftWater: Percy lampshades jumping from the St. Louis Arch in the first book, by saying that he is expecting the effect to be like hitting concrete when he strikes the water. But when he hits the water, he's perfectly fine and not injured in any way for a fall from a height that would certainly kill a normal person. Deliberately {{Justified}} because Percy is the son of Poseidon, so water ''cures'' him (remember earlier in the book that during the CaptureTheFlag game, Percy gets cut up by the Ares cabin boys, and his cuts heal the moment they contact with water) instead of killing him.
* SoProudOfYou
* SpellMyNameWithAnS: Canon example. The two first gods of earth and sky are Uranus/Ouranos/Ouranous and Gaia/Gaea.
* StarsAreSouls: In one novel, the goddess Artemis's {{Lancer}} is killed. She is honored with a whole constellation.
* {{Steven Ulysses Perhero}}: Several demigod children, including Travis and Connor "Stoll", the sons of Hermes, god of thieves, and Katie "Gardner" and Miranda "Gardiner" both daughters of Demeter, goddess of Agriculture.
* StuffedInTheFridge: Seems to be a recurring theme in Hades's family, what with being the God of the Underworld and all.
* SummonToHand
* [[SuperheroSchool Superhero Summer Camp]]
* SupernormalBindings: When Artemis is captured in ''The Titan's Curse'', she's briefly shackled before being forced to take Atlas' place holding up the sky.
* SuperReflexes: This is given as the reason why many of the demigods end up diagnosed with ADHD, because of their enhanced "Battle Reflexes". There is a similar explanation of dyslexia being the result of having a brain hardwired for ancient Greek; both were written in for the benefit of the authors son, who has both ADHD and dyslexia.
* SuspiciouslySpecificDenial: In the first book, Ares does this.
--> '''Ares:''' "I am the god of war! I take orders from no one! I don't have dreams!"
--> '''Percy:''' [[INeverSaidItWasPoison "Who said anything about dreams?"]]
* TakeThat: The Sphinx scene in ''Battle of the Labyrinth'' appears to be a TakeThat to U.S. education when she tries to administer a standardized test to Annabeth:
--> "Think? How am I supposed to test whether you can ''think''?"
** A much more blatant TakeThat comes from Thalia in ''The Titan's Curse''
--> "Ugh. Who picked the Jesse [=McCartney=]?"
* ThemeNaming: Sometimes coinciding with with puns. Other examples include Annabeth, daughter of Athena (and whose name contains 'Athena' plus a few extra letters), Clarisse, daughter of Ares (same case). Other examples include Nico de Angelo and, possibly, Ethan Nakamura ("village in the middle," i.e. [[spoiler:divided loyalties]]).
* ThickerThanWater
* TimeMaster: Kronos is an evil example of this.
* TitleDrop: In book 5 Hestia says: "I am here because when all else fails, when all the other mighty gods have gone to war, I am all that's left. Hearth. Home. I am the last Olympian."
** Count how many times the titular Sea of Monsters is referred to by name in ''The Sea of Monsters''.
** Happens in pretty much every book.
* ToHellAndBack: Percy has been to hell. Twice.
* TogetherInDeath: [[spoiler:Silena and Beckendorf.]]
* TooDumbToLive: Nearly everyone at times, but a particularly [[TVTropesDrinkingGame egregious]] example is [[spoiler: when they enter Hephaestus' junkyard and after explicitly being told not to touch or take anything, everyone does exactly that. Bianca's death was likely only because she drew the short straw offscreen.]]
** It's even worse for Grover. When told not to touch anything in the junkyard, his immediate response is to pick up a golden crown and bite a piece off! Guess his unconscious eating habits got the better of him.
* TookALevelInBadass: Nico, in ''The Titan's Curse'' after he realizes [[spoiler:he is so much more awesome than he thought.]]
** Also Percy, after [[spoiler:taking a dive in the river Styx]].
** Not only is [[ISeeDeadPeople Nico]] ''much'' more powerful than he's initially implied to be; he goes from being an annoying little kid to one of the most deadly demigods alive in under a ''year''. He's ''literally'' put himself through TrainingFromHell.
* TotallyRadical: Lots and lots of it, probably because it is told from the first-person narrative of a young teen, but actually written by a 40-something.
** Intentionally used in universe. This is how Percy realizes the true nature of the Lotus Casino, the kid he's playing with uses old slang that is way out of date.
* TroubledButCute: Nico di Angelo, [[spoiler: after his sister Bianca dies]].
* TrueSight: Certain characters can see through the Mist. These are special cases, like Sally Jackson and Rachel Elizabeth Dare.
* {{Tsundere}}: Several characters, the most notable being Annabeth (who is initially mean to Percy - whether this is due to him being a son of Poseidon or the fact [[spoiler:they end up hooking up]] is unknown) and Clarisse (''The Stolen Chariot'' side-story reveals her worst fear to be [[spoiler:her father's anger]]).
* TrailersAlwaysSpoil: If you see the cover of the first book, or the movie posters or trailers, and have ''any'' amount of Greek Mythology knowledge at all, you'll know that Percy is Poseidon's kid as soon as half-bloods are first mentioned.
[[/folder]]

[[folder:U-Z]]
* UndersideRide: In ''The Sea of Monsters'', Annabeth realizes that the sheep is Percy's way to sneak into Polyphemus's cave to rescue Grover and Clarisse. Promptly, we cut to Percy riding on the underside of Widget, one of Polyphemus's lighter weight sheep, as an invisible Annabeth tells him to hang on.
* UnderwaterKiss: [[spoiler: Percy and Annabeth.]]
* UnfortunateImplications: InUniverse. In ''The Sea of Monsters'', Annabeth explains that chain stores like Monster Donut multiply so rapidly because they are tied to a monster's life source. [[ParanoiaFuel Considering the existence of nationwide chains like]] [[Advertising/TheBurgerKing Burger King]], McDonalds, Wendy's, KFC, Dunkin' Donuts, Starbucks, and the like....
** In ''The Lightning Thief'' Percy stated that Gabe had threatened to "punch his lights out." Learning that he ''did'' hit Sally at the end of the book makes it likely that Percy was also abused by Gabe.
* {{Unperson}}: In ''The Titan's Curse'', when it was discovered that Zo Nightshade betrayed her sisters, the Hesperides, by helping Hercules, they kicked her out and any mentions of her were erased completely. It's implied, though, that she may have actually helped Hercules on all of his other nasty jobs, such as the Hydra and the Nemean Lion.
* UnwittingPawn: The gods,Half-bloods,practically everyone throughout the series has been used at some point
* UnusuallyUninterestingSight: After ''The Titan's Curse'', Percy and Annabeth both have matching streaks of grey in their hair from the effort of [[spoiler:holding up the sky]]. This is never mentioned again, and none of the people who show up later notice this.
** Many Demigod events that happen in public - you can have a fight with monsters and ''we'' will not notice anything. In ''The Last Olympian'', the reason why no one ever thinks Mrs. O'Leary is odd in Manhattan is because either they don't see her, or because Percy speculates that they actually see her as a truck of some kind.
*** A special mention goes to the "The Sword of Hades." While Percy was taking a test in the auditorium Mrs. O'Leary, a hellhound the size of a hummer, comes bounding in. Everybody else sees a poodle. Percy shocked that the mist
** The Laistrygonian fight in the start of ''The Sea of Monsters''. Seriously, the coach must be deaf if he can't see that the new "visitors" are very dangerous.
* UranusIsShowing: Averted because he is called Ouranos.
* VillainHasAPoint: Luke, Prometheus and most of the minor gods and demigods that side with the Titans do so because [[JerkAssGods the Olympians are jerks]], NeglectfulParents, and all around no better than the Titans. They side with Cronus either for revenge or hoping that by supporting him he will grant them a better deal.
* WeAreAsMayflies: Humans, from the perspective of the gods or any of the other mythological races.
* WeCanRuleTogether: Luke offers this to Annabeth and Thalia
* WeirdnessCensor: The Mist, eventually revealed in ''The Demigod Diaries'' to be controlled by [[spoiler: Hecate]].
* WeirdnessMagnet: Half-bloods have a 'scent' that mythological creatures (mostly monsters) can pick out and follow. If you are not strong and/or are unaware that something's weird about you, the scent is weak, enough to make monsters suspsicious enough to check it out but not enough to be ''certain''. But if you realize you are not normal, that intensifies the scent and can make monsters certain enough to attack; after that, you can basically count on monsters seeking you out in the real world and attacking every now and then. The reason you learn not to use cell phones is because cellular signals send messages to the monsters that say, "Here I am! Please rearrange my face!" At the summer camp/safe haven, most of the camp activities involve combat, fitness, and survival skills for good reason.
** ''The Demigod Diaries'' expands on this in the short story "The Son of Magic," wherein it's revealed that [[spoiler: Lamia]] cursed all Half-Bloods to be easily detected by monsters, in order to have revenge on Hera for cursing her.
* WellDoneSonGuy: Happens with plenty of half-bloods, but [[spoiler:Nico, in particular]].
** Percy, too. Grover points this out in the first book.
--->'''Grover (to Percy)''' "You're glad your dad is alive. You feel good that he's claimed you, and part of you wants to make him proud. That's why you [[spoiler:mailed Medusa's head to Olympus]]. You wanted him to notice what you'd done."
** This is also a major driving force behind Luke's actions.
* WhyWeCantHaveNiceThings: Percy, in the case of Gabe's Chevrolet Camaro, Paul Blofis's Toyota Prius, Meriwether College Prep's gym, the St. Louis Arch, Alcatraz, Mount St. Helens, Goode Middle School's band room...New York City...
* WhatMeasureIsANonHuman: Percy is much more willing to kill monsters than to kill humans. {{Justified|Trope}} because monsters come back to life eventually, just not in a very long time, fortunately.
** He also can't kill regular people, at least with Riptide. As he learns when cornered by a street gang in Los Angeles.
* WickedStepmother: [[spoiler:Subverted: Annabeth makes her stepmother out to be all sorts of resentful for bringing monsters around, but when we actually ''meet'' Mr. and Mrs. Chase in San Francisco...]]
** Smelly Gabe is a male version. Paul Blofis is a male ''subversion''.
* WigDressAccent: [[spoiler:Silena Beauregard's Clarisse disguise in the last book. Fooled at least the important people.]] It is explained that this worked specifically because they ''wanted'' to believe it.
* YeOldeButcheredeEnglishe: Zo replaces all of her (second person?) pronouns with this. Thalia gets extremely irritated with Zoe for this:
-->'''Thalia Grace:''' For ''you''. Not ''thee''.
-->'''Zo Nightshade:''' But you use ''you'' for the beginning of a sentence.
-->'''Thalia Grace:''' And the end. Not ''thou''. Not ''thee''. Just ''you''.
-->'''Zo Nightshade:''' ''[throwing her hands up in the air]'' I ''hate'' this language! It changes too often!
** This is an especially irritating example given that Zo is using the thee/thou set of pronouns ''wrong''. Though largely discarded now, they are the English familiar pronouns, like the t set of Spanish pronouns. Arguably FridgeBrilliance, given that Zo is not a native English speaker.
*** It also makes sense for her to use the familiar forms; she has little to no respect for heroes, so why would she use a more polite form of address, especially since they can't tell the difference anyway?
* WorldOfHam: It's a story about Classical Greek mythology, told in the style of a Classical Greek tragedy. This is almost a requirement.
* XMeetsY: ''HarryPotter'' meets ''ClashOfTheTitans''... and then some.
* YouCanSeeMe: Percy is shocked when Rachael can see both his sword and the skeletons chasing him.
* [[YouCantFightFate You Can't Fight Fate]]: Not often, but there are a few instances.
** It's lampshaded at one point. Annabeth tells the gods how trying to fight a prophecy almost never works (Yeah, Oedipus, ask your dad how that worked out), and the gods, who don't like being told ANYTHING very much, concede the point.
* YouKnowWhatYouDid: Early in ''The Lightning Thief,'' Percy's attempts to ask The Furies why they are attacking him are met with this.
* YouMonster: Subverted.
-->'''Annabeth''': You're a monster.
-->'''Geryon''': What gave it away? Was it the three chests?
[[/folder]]

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