[[quoteright:267:https://static.tvtropes.org/pmwiki/pub/images/thechronuschronicles.jpg]]

See that girl, the one with the bright red hair, overstuffed backpack, and aura of grumpiness? That's Charlotte Mielswetzski. And something extra-ordinary is about to happen to her. Oh, it's not the very cute kitten that appears out of nowhere and demands to go home with her. It's not the sudden arrival of her cousin Zee, who believes he's the cause of a mysterious sickness that has struck his friends back in England. It's not her creepy English teacher Mr. Metos, who takes his mythology lessons just a little too seriously. And it's not the white-faced, yellow-eyed men in tuxedoes, who follow Charlotte everywhere.

What's so extraordinary is not any one of these things....It's all of them. And when Charlotte's friends start to get sick one by one, Charlotte and Zee set out to find a cure. Their quest leads them to a not-so-mythical Underworld, where they face rhyme-loving Harpies, gods with personnel problems, and ghosts with a thirst for blood.

Charlotte and Zee learn that in a world overrun by Nightmares, Pain, and Death, the really dangerous character is a guy named Phil. And then they discover that the fate of every person -- living and dead -- is in their young hands.

Anne Ursu's trilogy of young adult fantasy novels--''The Shadow Thieves'', ''The Siren Song'' and ''The Immortal Fire''--focus on the Greek gods and monsters in the modern world. While the premise is similar to ''Literature/PercyJacksonAndTheOlympians'', this series looks upon Myth/GreekMythology in a rather different light.

!!Tropes present in ''The Cronus Chronicles'' include:

* AdultsAreUseless: Boy are they ever! In ''The Shadow Thieves'' Mr. Metos saves the cousins from the Footmen once, then gets captured by Philonecron and chained to cliff to have his liver eaten daily, until Zee rescues him. He's absent entirely from ''The Siren Song'', only sending Charlotte a letter (that arrives far too late to be helpful) warning her to stay away from the sea. In ''The Immortal Fire'', the Prometheans as a whole organization suffer from this when two displaced thirteen year olds can sneak around their secret base undetected ''and'' free a prisoner in their charge before escaping into London. (In fairness, they were rather short-staffed at the time).
* AncientArtifact: Hades's helm, Posiedon's trident, and Zeus's thunderbolt.
* BlackAndNerdy: Or at least, Black And Socially Awkward. Zee's an excellent footballer and thus instantly popular, but freezes up around any girl he fancies or who fancies him.
* CallingTheOldManOut: Steve to his father Zeus in ''The Immortal Fire'', for dumping his mom and being a pretty terrible absentee father.
* Myth/ClassicalMythology: What the series is based on.
* CoolOldLady: Grandmother Winter in ''The Shadow Thieves''.
* CreepyUncle: Though not related, Philonecron comes off this way towards Zee.
* EvilGenius: Philonecron is a self-proclaimed example.
* EvilGloating: Philonecron engages in this quite a bit.
* FateWorseThanDeath: Well, worse than what the Dead already suffer in Hades. Philonecron planned to throw all the mortal Dead into Tartarus, purely out of a fit of pique.
* FireForgedFriends: Zee and Charlotte, starting in ''The Shadow Thieves''.
* FieryRedhead: Charlotte
* FramingDevice: Each book has four parts, each with a clever title (ex. in ''The Siren Song'', the parts are called Fish, Fishy, Fishier and Fishiest).
* HenchmenRace: The eponymous shadows Philonecron stole are the souls of Zee and Charlotte's friends and fellow students, which Philonecron was using to make an army to overthrow Hades. His Footmen count as well, given he literally moulded them from clay to serve him.
* HeroicSacrifice: [[spoiler:Charlotte. It doesn't stick, but Zeus is bound to his oath on the river Styx anyway because of her intentions]].
* HoistByHisOwnPetard: [[spoiler:Poseidon transformed Sir Laurence Gaumm into a sea monster, who later grew so large he is able to destroy his yacht.]]
* InMediasRes: ''The Shadow Thieves'' is separated into four parts, the first opening from Charlotte's POV as she meets her cousin Zee and her fellow students start taking ill, one by one. The next chapter is from Zee's POV and starts half a year earlier, explaining ThePlague and why Zee was sent to live with Charlotte in the first place.
* JerkassGods: Almost all the gods (with the exception of [[spoiler:Persephone]]). The BigBad is a demigod who wants to enslave humanity, and most of the other gods either don't care or are actively trying to revenge themselves on the heroes for standing up to them. In the end the Charlotte [[spoiler:blackmails the gods into leaving humanity alone]].
* KillAndReplace: Zee is abducted for a week in ''The Siren Song'' and replaced with an... inexact double. During that time, he remains catatonic as the result of Philonecron's BloodMagic, mutely obeying commands, [[AndIMustScream trapped inside his own body]], as Philonecron reads to him, plays him classical music, expounds in great detail about his plans for world domination, and also feeds, bathes and dresses him. When Zee finally gets home, he finds that his parents' week-long business trip has been extended to several months, and no one even knew he was gone. It's absolute NightmareFuel.
* LemonyNarrator: Particularly in ''The Shadow Thieves''. It lightens up as the series progresses but never entirely goes away.
* LoverAndBeloved: Notable only for its [[AvertedTrope Aversion]] with Ganymede. [[NoYay Though one could make an argument for Philonecron's intentions towards Zee...]]
* ManOfWealthAndTaste: Philonecron, who buys hideously expensive imported mourning suits for his [[HenchmenRace Footmen]] and who never hesitates to insult the dress sense of everyone around him, particularly Charlotte. [[spoiler:Zee curses him to an amnesiac life as a sales clerk in a used suit store. It's a pretty fitting hell]].
* MartyrWithoutACause: Zee, who has a unique gift for convincing himself that everything from Charlotte's being grounded to the inevitability of death is his fault, and he should suffer for it.
* MeaningfulName: Philonecron. His name literally means "lover of death," from the Greek philo-, meaning loving, and nekros, meaning death or corpse.
* MyHeroZero: Zachary "Zee" Miller is referred to as Zero by [[SmugSnake Philonecron]] for being the 'starter', of sorts - his blood is used to animate the shadows that make up the villain's army.
* MysticalPlague: Zee is sent to America to get away from one of these, not realizing he is in fact, the carrier.
* TheNotLoveInterest: Charlotte and Zee towards each other. Though they're cousins, (and not the [[KissingCousins kissing]] variety) their relationship progresses the way a romance might in another story, with the two starting out awkward and unsure they can trust each other, and ending the series as the most important people in each others' lives.
* OnlyOneName: Aside from the immortals, it's implied that Mr. Metos and the rest of the Prometheans have only one.
* ParentalAbandonment: Zeus, to absolutely no one's surprise. [[HoistByHisOwnPetard It nearly kills him]].
* PlatonicLifePartners: Zee and Charlotte again.
* PluckyGirl: Charlotte
* ReasonableAuthorityFigure: Mr. Metos. [[WhatTheHellHero Most of the time]].
* RefugeInAudacity: When faced with the prospect of sacrificing a cow to request an audience with Zeus, Charlotte's disgust with gods' arrogance only deepens, so she dumps a cow patty in his alter bowl instead.
* ScrewDestiny: [[spoiler:Steve chooses to ignore his supposed destiny of overthrowing Zeus.]]
* SemiDivine: Steve, Jason Hart and the Prometheans all qualify.
* SeparatedByACommonLanguage: Not too much between Zee (who's British) and Charlotte (who's American) but there is a little bit of idiom confusion when they first meet, especially in regards to the football/soccer issue.
* SissyVillain: Philonecron loves fine dining, opera and silk shirts, tears up at the sight of his Footmen dressed up in their tuxedoes, and cattily snubs everyone else's poor taste in fashion. His [[NoYay obsession]] with Zee doesn't help.
* StevenUlyssesPerhero: See MeaningfulName
* TakeThat: The incompetent, egomaniacal head god Zeus describes himself as "The Decider". You may remember former president George Bush calling himself the same thing.
* TeenGenius: Steve is excellent at Quiz Bowl and is able to ace a test without putting much effort into the class, leading the teacher to accuse him of cheating.
* TheUnfavorite: Not that being [[CreepyUncle Philonecron]]'s favorite is a good thing, but he absolutely ''loathes'' Charlotte, considering her his archnemisis, and is surprisingly petty towards her compared to his obsessive affection for Zee.
* WhatTheHellHero: Charlotte and Zee are understandably horrified at the Prometheans' plan to [[spoiler:sacrifice Steve to save humanity]].
* YouAreGrounded: This happens to Charlotte after she is unable to explain their nightlong absence.