%%Zero Context Examples will be commented out until further context is given to them.

[[folder:A]]
* AbhorrentAdmirer: Grunhilda, to Gaius. Vivian, to Arthur (by the end of the episode at least).
* AbortedArc:
** Why Aithusa sided with Morgana was never explained.
** In Series 2, Merlin tries to stop Mordred fleeing from Camelot's army. In response, Mordred kills the two soldiers chasing him and coldly tells Merlin via telepathy that he will never "forgive or forget" what he did. When he returns in Series 5, he's completely forgotten about it.
** For the first two series it was treated as a pretty big deal that a) Arthur was born of magic, and b) he didn't know about it. It was built up to be a revelation that would shake-up the show, particularly in regards to Arthur's views on magic. The likes of Uther, Nimueh, Gaius, Merlin, Morgause and the ghost of Ygraine all play a role in this mini-drama, but once Merlin convinces Arthur that the ghost he saw of his mother (who tells him the truth) was simply a trick, the entire thing is dropped and never brought up again (unless you count a throwaway line in series 4).
** The first two series also sets up a growing sense of animosity between Merlin and the Great Dragon, with Merlin often refusing to follow the Dragon's instructions based on his own personal sense of right and wrong. It seemed like it was heading for a schism between the two characters, in which Merlin would decide to follow his own path instead of blinding following destiny (especially regarding some of the ''incredibly'' dodgy stuff the Dragon tries to get him to do), but at the start of series three this is all forgotten, and Merlin never questions the Dragon's word again.
* AbortedDeclarationOfLove: Arthur seems to be on the verge of telling Guinevere that he loves her in the series three finale. However, she interrupts him after he makes the mistake of saying "if I never see you again..." which only compels her to insist that they ''will'' meet again.
* AbusiveParents: Uther. It is obvious that many of Arthur's insecurities stem from being raised by an emotionally distant and cold father. The same could be said for Morgana and her emotional, mental and psychological issues. Although Morgana was never really mistreated by Uther, the way Uther talked about magic users like Morgana definitely contributed to Morgana's FaceHeelTurn in season three.
* ActionDad: Uther. He's always involved in the action in regards to Camelot.
* ActionFashionista: Morgana.
* ActionGirl: Morgana and Morgause, who are later [[DarkActionGirl Dark Action Girls]]. Gwen to a lesser extent. Also Enmyria, the bandit girl in ''[[Recap/MerlinS02E11TheWitchsQuickening The Witch’s Quickening]]'', and [[Literature/TristanAndIseult Isolde]] in ''[[Recap/MerlinS04E13TheSwordInTheStonePartII The Sword in the Stone Part II]]''.
* ActionHero: Merlin, Arthur and all of the Knights at the Round Table. They all use combat as a way to solve problems and missions.
* AdaptationalAngstUpgrade: Perhaps not so much an "upgrade" as a "shift" in what the main characters angst about. Arthur has [[WellDoneSonGuy Daddy Issues]], Morgana grapples with fear of her growing magical powers, Guinevere is given a RagsToRiches story, Merlin has to hide his true identity while making SadisticChoice after SadisticChoice. Their legendary counterparts had [[BecauseDestinySaysSo Depressing Destinies]], BrotherSisterIncest and [[LoveTriangle Love Triangles]] to contend with.
* AdaptationalAttractiveness: In the original Arthurian legends, Merlin is portrayed as an [[WizardClassic old, eccentric and zany wizard]]. But in this version, [[PrettyBoy Merlin]] is [[MrFanservice youthful, attractive and appealing to the female audience]].
* AdaptationalProtagonist: Merlin the wizard becomes the main protagonist instead of the future King Arthur in this prequel/adaptation of the Myth/ArthurianLegend. While Arthur plays a major role, the series is more concerned with Merlin's magical shenanigans, rivalries, and his attempts to guide Arthur.
* AdaptationalVillainy: Obviously it depends on what source material you're working with, but the likes of Morgana, Morgause, Mordred, Nimueh and Agravaine can be portrayed much more sympathetically in various legends and other adaptations than they are in this series.
* AdultsAreUseless: Uther's the bloody ''king'', for crying out loud. Though he apparently was ''very'' good at killing everyone with magic.
** Subverted with Gaius. Played straight with everyone else even if, in typical showbiz fashion you [[DawsonCasting shave a few years]] off the actors real ages they're still in their late teens (Merlin) to mid twenties (Gwen) so maybe "Authority Figures Are Useless" would be more accurate.
* AesopCollateralDamage: Arthur has been cursed in an episode after he killed a unicorn and didn't even show any remorse. Which would have been fine, except for that this just leads to his innocent subjects suffering from hunger and thirst (all the crops suddenly wither and all the wells dry out at the same time) until things are back to normal by the end of the episode. Unusually, it is actually stated in this case that the collateral is completely unfair. The innocent poor people shouldn't have to lack both food and water, just so their crown prince can learn a lesson about not being arrogant!
* AllJustADream: Episode [=3x10=] opens with Gwen becoming Queen of Camelot with Arthur as king, but it is shown that it is just a dream of Morgana's [[spoiler: though this dream comes true in the series 4 finale]].
* AllOfTheOtherReindeer: Everyone except Merlin and those who know his secret, like Gaius and Lancelot.
* AllTrollsAreDifferent : Lady Catrina, "Beauty and the Beast".
* AllYourBaseAreBelongToUs: Series 3 and 4 both use this for the finale.
* AlienBlood: Troll blood is green, apparently.
* ALightInTheDistance: Arthur in the caves, looking for the mortaeus flower.
* AlmightyJanitor: Merlin. Big time.
* AlmostKiss: Arthur and Gwen in ''The Castle of Fyrien'' and at the end of ''Queen of Hearts''. They actually ''do'' manage to get there earlier in the latter episode, but are interrupted just as they're getting started.
** Alvarr and Morgana in ''[[Recap/MerlinS02E11TheWitchsQuickening The Witch’s Quickening]]''.
* AloofDarkHairedGirl: Morgana.
** Freya could count as well.
* AlwaysSaveTheGirl: Arthur, Merlin and Lancelot have all been willing to give up what is most important to them in order to save Guinevere; respectively, his entitlement to the throne, his magical secret, and his life.
* AlwaysSecondBest: Arthur and Lancelot have this mentality in regards to each other, each believing that the other is "the better man" in everything from their skills in combat to how Guinevere feels about them.
* AmbitionIsEvil: Morgana, after her FaceHeelTurn from a compassionate young woman into a villain. After this, she thirsts for power, devotes herself to becoming Queen of Camelot, and gaining entitlement to the throne at any cost, including trying to kill her own half-brother (Arthur). She turns against her [[TrueCompanions friends]], including her best friend (Gwen). Ultimately, her hunger for power turns out to be her ultimate downfall.
* AnachronismStew: It pretty much turns Anachronism Stew up to eleven. When the creator was criticized for it, he pointed out that it isn't supposed to be historically accurate. People complain about the [[MisplacedVegetation tomatoes]], he said, but oddly enough no one's commented on the dragon.
** Knights in plate armour and huge stone castles in pre-Saxon England.
*** Although weirdly the plate armour tends to only cover one shoulder, and [[ArmorIsUseless often doesn't hold up to anything]]. And no one appears to use [[ShieldsAreUseless a shield]], unless they're in a tournament.
** On another equipment-related note, Camelotian guards are equipped with billhooks and Norman helmets without nasal guards. The weaponised version of the billhook did not appear in Western Europe until at least the Viking Age (the agricultural tool was present for a long time though, maybe as far as the Neolithic Age), and it certainly was not standard issue in neither English nor Welsh armies until at least the mid-1200s. Though admittedly it does give them [[ArtisticLicenseHistory a distinctive look and the billhooks are a nice fit for a guard weapon]].
** Gaius' medical knowledge being far too advanced for the time period.
** Gwen's kidnappers use [[InstantSedation chloroform]]. I mean, "compound of hog's wart."
** In ''Lady of the Lake'', Arthur appears to be having pre-packed deli meat for breakfast. Oddly enough, in the same episode, when Merlin steals the original meal and replaces it with food from a cupboard in Gaius's quarters, one of the components is a shriveled, close-to-rotten whole apple... an uncomfortably realistic detail of medieval life.
** Parodied in the 2009 Series/ChildrenInNeed special, in which the kingdom is invaded by "magical items" like microwaves, hairdryers and mobile phones. See it [[http://youtu.be/vJhixrsFO1Y here]].
** French chivalry in the middle of Dark Ages Britain. Although you can't blame them for that one, that was in the original myths.
** And let's not forget the infamous aluminium beer cans on the table in ''Lancelot and Guinevere''.
** As well as the coat hangers, which didn't appear in that form until the 1900s.
* AndStarring: John Hurt as the voice of the Dragon.
* AnguishedDeclarationOfLove: By Arthur, to Merlin, about Guinevere.
** Another more subtle one by Lancelot, also to Merlin, ''also'' about Guinevere in [[Recap/MerlinS04E02TheDarkestHourPartII The Darkest Hour Part II]].
* AntagonisticOffspring: Morgana towards Uther.
* AntiHero: Almost everyone can be considered Type III, due to the show being in the Middle Ages where killing and not losing sleep over it is the norm. Adjusting, most of the knights and Arthur are Type I or Type II with a side of HeroAntagonist.
** Even adjusting for DeliberateValuesDissonance, Merlin is an ''extremely'' dark Type III. He's not vicious enough to move into Type IV, but GoodIsNotSoft is in full play here.
* AntimagicalFaction: Personified in King Uther.
* AntiVillain: Several of the villains in the series. Uther was a genocidal tyrant but he also genuinely loved his children and cared about his people. Morgana, Mordred, and most of the Villains of the Week attack Camelot because of its laws that persecute them.
* AnyoneCanDie: The first three episodes of Series 4 see the deaths of [[spoiler: Morgause, Lancelot and Uther]].
** Series 5 kills off, in order: [[spoiler:Elyan, Mordred, Gwaine, Morgana and Arthur]].
* ApologisesALot: Merlin.
* AppliedPhlebotinum: Oh, Gaius.
* ArchEnemy: Merlin to Morgana and vice versa. According to The Great Dragon, Morgana is [[DarkMessiah the dark]] to Merlin's light and the hatred to Merlin's love.
* ArcSymbol: The Round Table. Hints of it turn up throughout the first four seasons - Arthur gathers villagers in a circle around him and tells them that they're all equal, his knights form a circle around him when he asks for volunteers to help him fight the dragon; and he gathers all his closest allies around a circular stone table while they're on the run and tells them that it symbolizes the way they all worked together. Finally appears in season five in the hall of Camelot Castle, with everyone gathered around.
* ArcWords: “We ride at first light.”
* ArmourIsUseless: DependingOnTheWriter.
* ArrangedMarriage : Arthur and Elena.
* ArtisticLicense:
** Despite centuries of characters added with the retelling of the Arthurian myths this TV show opted to still add the character Gaius who was made up for the series.
** In ''[[Recap/MerlinS01E07TheGatesOfAvalon The Gates Of Avalon]]'' Gaius states that a staff had Ogham script on it, then show the page. The script shown does carry the same format as Ogham in that there is a line connecting all the letters and it is a series of lines, but the props department then embellished the script by making it much more TV friendly (most of Oghams' letters are a series of 1-5 dashes connected on a line, the script shown only had the vaguest basis on Ogham.
** In ''[[Recap/MerlinS01E12ToKillTheKing To Kill The King]]'' Gaius talks about a magic stone that has been lost for 1000 years. Said stone has writing on it, in Anglo Saxon runes, which are from two hundred years after the time period of Arthurian myth. 1000 years before THAT the writing the writing would have been in the Euboean alphabet. Or at least cuneiform.
** The nature of Merlin's job in the first place. Even in TheDungAges, Merlin's tasks would likely be divided up into a retinue of different servants, and it would be unlikely in a freaking ''palace'' to have the guy dressing you in the morning to also be serving you dinner, mucking out the stables, and uh, acting as your sparring partner/punching bag. Realistically, Merlin appears to do two or three different jobs at the palace ''while'' somehow apprenticing with Gaius on the side ''while'' saving the realm on a regular basis.
* AwesomeMomentOfCrowning: The FlashForward to Guinevere's crowning.
** [[spoiler:Arthur's crowning in 4x03.]]
** [[spoiler:Then Gwen's actually happens in the season finale.]]
* AwfulTruth: The circumstances of Arthur's birth.
* AwLookTheyReallyDoLoveEachOther: Arthur and Merlin may insult each other like no tomorrow, but deep down, they really do care for each other and are willing to sacrifice themselves to protect the other.
** Ditto for Arthur and Morgana in season one.
* AutomatonHorses: In a sense. They're used a lot, but we never see them getting groomed or fed or watered.
** Merlin mucking out the stables is a running gag, though. In ''Aithusa'' Merlin has to forgo his own dinner to feed the horses. And in ''Sword in the Stone Part 1'' Merlin has [[spoiler:simpleton!]] Arthur rub down the horses. So caring for the horses is definitely there, but LawOfConservationOfDetail often {{Hand Wave}}s it.
** Horses also seem to vanish completely when not needed--for example, whenever Arthur and Merlin are going somewhere and need to continue on foot, or when they ride out with a half-dozen or more red-shirt knights and return alone. It's especially jarring when both things happen in sequence--the horses vanish, the party walks to the next plot point, the red-shirts are slaughtered, and the next scene is Arthur and Merlin riding back to Camelot, having apparently collected their own mounts but left all of the others behind.
[[/folder]]

[[folder:B]]
* BackForTheFinale: At the end of series three we get reappearances from [[spoiler:Lancelot, Elyan, Gwaine and Freya]].
* BadBoss: Arthur can appear as it towards Merlin, but it's mostly for comedic effect. Morgana to Agravaine, and it's played seriously.
* BadassAdorable: Merlin, OH SO MUCH.
* BadassBoast: In ''Aithusa'', when Gaius' power hungry and traitorous former pupil scoffs at Merlin's assertion that the Dragon's egg should not be used as a tool, Merlin comes up with this gem [[spoiler: just before he blasts him into a wall]]. The OhCrap look on the man's face just makes the scene.
-->'''Merlin''': I am the last Dragon Lord. And I am warning you -- leave this egg alone.
* BadassBookworm: Merlin. He reads and researches alot and spends a lot of time with his nose in a book when he is not saving Arthur or doing chores for Gauis.
* BadassBystander: Watch the fight scenes in ''[[Recap/MerlinS01E10TheMomentOfTruth The Moment of Truth]]'' carefully. There's a blonde girl in there that ''kicks ass''.
** Although it's debatable as to what extent they could be called "bystanders", Sir Owaine and Sir Pellinore in ''[[Recap/MerlinS01E09Excalibur Excalibur]]'' take up Sir Tristian's challenge to a duel in order to prevent Arthur from doing so, and go to certain death as a result.
* BadassCape: The red capes with a embroidered golden dragon of the Camelot knights, though it ironically makes them a literal RedShirtArmy.
%%* BadassCrew: The Knights of the Round Table.
* BadassFamily: The Pendragons. Uther, Arthur and Morgana are all trained in combat and master swords people. However, they are also a BigScrewedUpFamily.
* BadassInDistress: ''Everyone'' on this show has needed rescuing at some point, and [[WorldOfBadass everyone is a badass in their own way]]. Even Merlin, who can stop time and kill you just by looking at you, has needed rescuing at least twice.
%%* BadassLongcoat:
%%** Arthur's got a brown one.
%%** Uther has one, too.
%%** Tristan wears one that's similar to Arthur's.
* BadassLongrobe: Merlin in his Dragoon disguise.
%%* BadassNormal:
%%** Arthur.
%%** Uther is pretty badass too.
%%** Also, Lancelot. Episode 2x04 might as well have been called "The Lancelot Show."
%%** Gwaine kicks ass and takes names and he does it with style.
* BadBadActing: Merlin in episode 3x07 when he finally [[HintDropping takes a hint]] and leaves Arthur alone with Gwen.
--> '''Merlin''': The wolves!
** When Arthur announces his engagement to Princess Mithian, [[ShipperOnDeck Merlin]] manages an [[TheUnSmile unsmile]] at best.
* BanOnMagic: At the start of the show, magic is illegal in Camelot, forcing Merlin to hide his powers while trying to help Arthur survive.
* BalancingDeathsBooks: Basic rule of the Old Religion is a life for a life (it seems that the life of the person most important to the one who asks will be taken, hence Igraine dies because of Uther's request for a son, and Hunith nearly dies because Merlin asks for Arthur to be spared).
* BallisticDiscount: In "Gwaine", [[ShameIfSomethingHappened protection racketeer]] [[NamesToRunAwayFromReallyFast Dagr]] uses his new magic sword to reclaim the purchase price by stabbing the seller in the back.
* BallOfLightTransformation:
** The Sidhe, [[OurFairiesAreDifferent which in this series are small blue-skinned fairies]], often appears as small, blue balls of light flying around.
** In the episode [[Recap/MerlinS03E03GoblinsGold "Goblin's Gold"]], the title goblin can turn into a mote of light. He uses it to escape pursuit and fly through walls, but also to enter a human's body and attempt [[DemonicPossession possession]], successfully with Gaius.
* BarBrawl: A ''Medieval'' bar brawl at the beginning of 3x04.
* BarSlide: When Gwaine first appears in 3x08, he's being slid across the bar.
* BastardBastard: Morgana after her FaceHeelTurn. She is the illegitimate daughter of Uther and Vivienne.
* BattleButler: Merlin, even if Arthur doesn't realize it.
* BattleCouple: Morgause and Cenred, with a little BelligerentSexualTension thrown in, although it's averted in 3x12.[[YouHaveOutlivedYourUsefulness And how.]]
** Tristan and Isolde in 4x13.
** King Arthur and Queen Guinevere.
* BattleOfWits: From Series 3 onward, often between arch-enemies Merlin and [[FaceHeelTurn Morgana]], who are the two most powerful characters in the series. Before Arthur and Gwen become King and Queen, Merlin was the one person who prevented Morgana from completely destroying Camelot.
* BeCarefulWhatYouWishFor: In the first episode, Merlin [[DesperatelyLookingForAPurposeInLife angsts about having no purpose for his abnormal power]]. The Dragon gives him one, and what follows is endless [[KickTheDog killing and questionable decisions]].
* BeautifulDreamer: Almost every character has watched either Merlin or Guinevere sleep at one stage or another. The most notable examples are when Merlin lends Gwen his bed in ''[[Recap/MerlinS01E12ToKillTheKing To Kill The King]]'' and then stays by her as she sleeps, and when Arthur finds Gwen under a sleeping spell in ''[[Recap/MerlinS02E12TheFiresOfIdirsholas The Fires of Idirsholas]]'' he watches her for a few moments after putting her on Morgana's bed.
* BeautyIsBad: With few exceptions [[spoiler:Freya, Mithian]], every single beautiful woman on the show ends up being a villain, or is at least meant to be perceived as unsympathetic.
** Subverted marvellously with [[spoiler:Princess Mithian]]. You'd think they would have made her as unpleasant as possible so Arthur would come and throw himself at Gwen again but she's actually rather nice.
* BecameTheirOwnAntithesis: Arguably the premise of the show.
** Morgana, from a compassionate young woman into one of the series' primary villains.
** Lancelot during his shade episode.
** Merlin changes rather dramatically as well. He became progressively darker and edgier. Surprisingly, he did not do a FaceHeelTurn the way Morgana did.
* BecauseDestinySaysSo: The CentralTheme of the series.
* BeleagueredAssistant: Several times Merlin had to help bail Arthur out of some sticky situations. Particularly in the episode ''[[Recap/MerlinS01E07TheGatesOfAvalon The Gates Of Avalon]]'', where poor Merlin had to deal with the consequences of a spellbound Arthur courting Sophia. In this one episode alone, Merlin got placed in the stocks ''[[RuleOfThree three]]'' times!
* BerserkButton: Even if you ''are'' an incredibly powerful sorceress, do not try to kill Gaius with magic in front of Merlin. Of the two who have tried so far, one was telekinetically hurled into a pillar at neck-breaking speed, and the other was struck in the face by lightning.
** It is generally considered a bad idea to harm Morgause in front of Morgana. She doesn't like it. At all.
** Mess with a certain maid-servant and you'll have to deal with her best friend (a powerful warlock), her boyfriend (the crown prince), and a team of the best knights in the land. Best to just leave her be...
** Also... messing with Merlin will result in [[TheGoodKing Arthur]], [[PapaWolf Gaius]], [[GiantFlyer The Great Dragon]], [[KnightInSourArmor Gwaine]], [[KnightInShiningArmour Lancelot]] ''and'' [[MamaBear Gwen]] unleashing hell on you.
** As ''Lancelot du Lac'' has demonstrated, [[spoiler:kissing Gwen, the love of his life]], is the best and quickest way to drive a composed and compassionate Arthur into a [[CrazyJealousGuy blind,]] [[MurderTheHypotenuse murderous rage.]]
** And we can't forget Uther, where magic is concerned.
** It is also generally a bad idea to mess with Hunith, Merlin's mother.
** Also, we cannot forget Arthur when he is called fat and later, actually turns out to be fat!
* BettyAndVeronica: Arthur and Lancelot for Gwen with Lancelot as [[NiceGuy the friendly]] and noble commoner and Arthur as the [[JerkWithAHeartOfGold arrogant dollophead]] [[UptownGirl prince she can never have]].
* BewareTheNiceOnes: Merlin, whenever someone close to him is threatened.
** Gwen, [[MamaBear when Merlin is threatened.]] ''"GET AWAY FROM HIM!!!"''
** Mordred, especially in Series 2. Yikes!
** A seemingly all-powerful Future Merlin, standing triumphant over her on the field of battle, a staff in hand and a look of utter TranquilFury, literally becomes the stuff of nightmares to Morgana in Series 4.
---> '''Morgana''': Help me, Emrys! Please!\\
'''Merlin''': Is this ''really'' what you wanted, Morgana?!
** Morgana, herself. She was once one of the nicest characters on the show, but even then demonstrated she could be a dangerous adversary. Unfortunately, she became not so nice later on.
* BewareTheQuietOnes: Mordred. When Mordred was a child, he didn't talk much, if ever. But he smashed a mirror with his powers when he was angry and upset over one of his kind being executed. That was a clear sign to not mess with this kid.
* BigBad:
** Season 1: Nimueh
** Season 2: Morgause
** Season 3: Morgause and [[spoiler:Morgana]]
** Season 4: [[spoiler:Morgana]]
** Season 5: [[spoiler:Morgana...do we see a pattern?]]
* BigBadEnsemble: Morgana was paired up with a different cohort once per season; first with Morgause, then Agravaine, and at the very end with Mordred. Then there were the MonstersOfTheWeek, who were usually out to seek revenge against King Uther, who was himself something of a villain.
* BigBadassBattleSequence: "The Tears of Uther Pendragon: Part Two". Specifically, the siege on Camelot.
* BigBrotherInstinct: Kilgharrah's treatment of Merlin in Series 2 is best described as a come and go fondness. In Series 3, [[spoiler: after becoming spiritual brothers, Kilgharrah burns up Serkets trying to kill Merlin, doesn't want him to leave the cave until he's fully recovered, and allows him to ride him despite the fact that the series 3 finale shows he detests being used as a horse.]] He still occasionally treats him like an idiot, but given that we have only one [[spoiler: talking]] dragon to draw references from, this could have been a normal big brother relationship among dragons.
** Arthur and the Knights of the Round Table, especially Gwaine and Lancelot, are fiercely protective of Merlin. Justified in that he physically looks small, fragile and scrawny and is also a few years younger than all of them, but still funny considering he could kill all of them easily with just a wave of his hand.
** Arthur, after barely knowing Mordred a few weeks, is already showering him with attention, praising him and going to insane lengths to save his life -- lampshaded by Merlin and Gwen. "The Disir" ends with an adorable moment of them sword-fighting and then Arthur lifting Mordred up in the air, goofing off like a big brother with his little brother. It's oddly fitting, considering in the myths Mordred was supposed to be Arthur's son.
** Merlin also had this towards young!Mordred, Daegal and Gilli.
* BigBrotherMentor: Arthur probably fancies himself as this to Merlin, though Gwaine or Lancelot probably fit the bill better.
** Arthur ends being one for [[spoiler: Mordred. Gwen points out he's growing fond of the boy, and Arthur couldn't shut up on what a promising knight Mordred is]].
* BigDamnHeroes: Merlin and Arthur, usually. Occasionally Morgana, Gwen, Gaius and Lancelot.
** Every good character in The Coming Of Arthur Part Two.
* TheBigDamnKiss: Arthur and Gwen's first kiss came complete with dramatic lighting and an orchestra of violins.
** Heck, it's more noteworthy when one of their kisses ''isn't'' a [[TheBigDamnKiss Big Damn Kiss]].
* BigEntrance: Morgause and Mithian both get fairly impressive entrances onto the show. Tristan de Bois as well when he interrupts Arthur's crowning ceremony by leaping through a stained glass window on horseback.
* BigFancyCastle: Castle Camelot - which is actually Pierrefonds, a ''real'' BigFancyCastle.
* BigNo: [[spoiler:When Gaius dies for Merlin and Merlin rushes to his side only to find him dead ''already'', Merlin says "Nnnnnnoooooo!" twice. Except that Gaius wasn't '''actually''' dead.]]
** Morgana lets out an absolutely humongous one when [[spoiler: Morgause is apparently killed; seriously, we're not kidding, it '''''LITERALLY''''' brings the roof down. Literally.]]
* BigScrewedUpFamily: As of the end of series three, the Pendragons definitely qualify, what with Uther and Arthur's strained relationship and the fact that Morgana is not only [[spoiler: Uther's illegitimate daughter and Arthur's unacknowledged half-sister, but actively trying to kill them both]]. Both of Arthur’s [[EvilUncle uncles]] tried to avenge Ygraine’s death: Tristan by coming back from the grave to kill Uther and [[spoiler: Agravaine by plotting with Morgana]].
* BilingualBonus: The spells are in Anglo-Saxon.
* BitCharacter: Geoffrey of Monmouth, who started out as the court genealogist, but who now also serves as MrExposition whenever Gaius isn't around, and is trotted out whenever the writers need someone to preside over a coronation or wedding. He even seems to be a member of the council, and is the one who backs up Guinevere in ''The Darkest Hour''.
** Also Audrey, the head cook of Camelot's castle kitchens, and Isildur, a druid leader. Both have appeared in [[RuleOfThree three episodes each]].
* BitchInSheepsClothing: Sophia.
** And more recently, [[spoiler:Morgana.]]
** Lamia.
* BittersweetEnding: The end of series three. Though [[spoiler:the Knights of the Round Table and Guinevere return to Camelot in triumph, the hug that Arthur and Guinevere share is clearly marked by their sadness over Morgana, and Merlin's smile fades as he watches them, no doubt reminded of Freya.]]
** [[spoiler: The entire series pretty much ends like this, Morgana has finally been defeated for good and Camelot is safe, but Arthur was killed in the process along with Gwaine. In addition, the epilogue shows that ''everybody'' Merlin once knew is now dead. Nevertheless, the fact that Merlin is still alive means he's waiting for the day when Arthur will rise again at the day of Albion's greatest need.]]
*** [[spoiler: Its worse when you think about it. The Golden Age may never have come to pass since Arthur was supposed to bring it about. Albion is not united so other kings may invade thinking Gwen weak. The Saxons are still a threat. Gaius can only have a few years left. Magic users would still hate Camelot. Merlin is no longer around to help protect Camelot. Arthur's whole return may have been made up by The Great Dragon to comfort Merlin or he might have been wrong. He was wrong on other things. ]]
* BlackAndGreyMorality: Uther hunts down anyone related to magic, even healers, even children. He's a cruel dictator. Getting rid of him would be a good thing. However the villains trying to kill him, [[spoiler: Morgana and Morgause]], have some evil tendencies in a WellIntentionedExtremist way. They will kill others, but only if they have to to get to Uther or [[spoiler: Arthur]] later.
* BlackDudeDiesFirst: Tom, Gwen's father, is arguably the first significant death in the series.
* BlackKnight: Sir Tristian in ''[[Recap/MerlinS01E09Excalibur Excalibur]]''.
* BlackMagic: Morgana, Morgause, Nimueh and Mordred all practice Dark Magic.
* BlackVikings: Guinevere, her father, brother and Sir Pellinore are all black. However, they also have dragons and fey. It's also not so much of a stretch as people think, as there is evidence of some black people in medieval England. Of course, none were knights or queens that we know of.
* BlingOfWar: Morgana's "action gear" involves a shiny metal corset of some kind. Unless she were shot directly in the stomach, it's utterly impractical.
* BloodlessCarnage: Plenty of people die in this series, but you will rarely see any of them actually bleed.
* BluffTheImpostor: Arthur does this to goblin-possessed Gaius - he talks casually about Merlin's uselessness and impending death sentence, and when "Gaius" isn't bothered, Arthur knows something's up.
* BodyMotifs: There's a large emphasis on hands and eyes. Magic-users have [[SupernaturalGoldEyes Golden Eyes]] when they perform magic, whilst [[HeldGaze Held Gazes]] and HoldingHands denotes love and trust.
* BoisterousBruiser: Arthur. He is hot headed, courageous and impulsive.
* BondingOverMissingParents: Merlin and Gwaine bond over their dead fathers, Arthur and Elena bond over their dead mothers.
** And Merlin and Arthur bond over one of them having a missing father and the other a missing mother.
* BookEnds: In the first episode of series two Guinevere saves Arthur's life from a flying gargoyle in the castle courtyard by tackling him to the ground. In the last episode of series two Arthur saves Guinevere's life from a flying dragon in the castle courtyard by tackling her to the ground.
** In the first episode of series three Merlin is witness to a hug between Arthur and Morgana; in the last episode he watches a similar embrace between Arthur and Guinevere.
** In both the opening and the closing two-parters of Series 3 Camelot was attacked by an army of immortal soldiers sent by Morgause and Cenred.
** Arthur is [[spoiler:crowned King]] at the beginning of series 4; Guinevere is [[spoiler:crowned Queen]] at its conclusion.
** The beginning of Series 1 sees Merlin walking on a road to Camelot; [[spoiler:the end of Series 5 sees older!Merlin walking on a road in the same manner, waiting for Arthur.]]
* {{Bookworm}}: Merlin. He is always reading and researching a lot.
* BoyMeetsGirl: Merlin meets Freya, he falls in love with her, Freya falls in love with him and they are so incredibly happy. [[spoiler: Except it [[StarCrossedLovers ends in tragedy when Freya ends up dying.]]]]
* {{Brainwashed}}: This happens to Arthur in at least three episodes, with the first case bordering near BrainwashedAndCrazy. In the third case, [[spoiler:it's by Merlin]]. Then it happens with [[spoiler: Gwen]] in season 5.
* BrainwashedAndCrazy: In ''A Servant of Two Masters'' in series 4, Merlin [[spoiler:is bewitched by Morgana to kill Arthur, but is thankfully a terrible assassin.]]
** The knights in "Lamia". They start fighting each other, being ''incredibly'' disrespectful to Merlin (to whom they're usually [[CoolBigSis Cool Big Brothers]], and threatening Merlin and Gwen for speaking out.
** In season five, Morgana is at it again, this time with [[spoiler: Gwen]].
* BreakTheCutie: Morgana. Goes through a season of terror only to have [[spoiler: the one person in Camelot she could trust poison her.]] Ouch. Not to mention being [[spoiler: trapped in a pit for about two years straight. With a growing dragon. And in chains.]]
** Averted by Merlin, thanks to being an IronWoobie. But let's face it, half the reason he hasn't gone into total breakdown is because of his potential to be a terrifying WoobieDestroyerOfWorlds if he did.
** Guinevere in ''Lancelot du Lac'', in which [[spoiler: she is enchanted into betraying Arthur by Morgana, is banished from Camelot and none of her friends are there to see her off except Merlin. Not even her own brother wants to see her. The cherry on top? Only the audience and the villains know she was enchanted, so she believes everything is her fault]]. This isn't so much BreakTheCutie as smash her to bits, stomp on the pieces, and grind them to dust. As if that isn't enough, she gets [[spoiler: enchanted AGAIN by Morgana to kill Arthur and was probably tormented a bit while she was held captive.]]
** Aithusa. Being trapped in a pit you outgrow and end up barely able to even move in at all will do that to you.
* BreatherEpisode: ''[[Recap/MerlinS02E10SweetDreams Sweet Dreams]]'', which was a romantic comedy of sorts jammed between a Witchhunt episode, Arthur almost killing Uther, Merlin losing his first love and Morgana's StartOfDarkness.
** 3x03 Goblins' Gold, which comes after the dramatic two-part series opener where Morgana returns and Camelot is nearly destroyed.
* BreathWeapon: The Great Dragon and Aithusa both shoot fire from their mouths as a defence weapon.
* BrickJoke: the Sidhe staff Merlin takes from Sophia in ''[[Recap/MerlinS01E07TheGatesOfAvalon The Gates Of Avalon]]'', which he uses again in ''[[Recap/MerlinS01E12ToKillTheKing To Kill The King]]''.
** It doesn't appear again until ''The Changeling'' in series 3.
** Mmm, rat.
** Gaius constantly telling Arthur that Merlin is in the tavern when he disappears to do his magical thing.
* BrokenBird: Freya, Morgana, Gwen, and Merlin (as a RareMaleExample) are all examples.
* BrokenMasquerade: In series 3, Uther indirectly admits he knows Gaius was a sorcerer in the past, when he asks him to do anything, even ''magical'' to save Morgana.
* BuffySpeak: Merlin is the biggest offender.
* BuildingOfAdventure: Lots of crazy stuff goes down in Castle Camelot.
* BullyingADragon: Quite literally, in one case. Metaphorically, it often happens elsewhere. Merlin tries to play this in the first episode by warning Arthur he doesn't want to see what he's capable of. But since he can't use his magic in public, it was a pretty futile threat, and Merlin just ends up getting his ass kicked.
** Although in the literal example, said dragon ''does'' take a shot at incinerating Merlin, and Merlin magically blocks the fire.
* BumblingSidekick: What Arthur ''thinks'' Merlin is, due to his WrongGenreSavvy issues. In reality, Merlin is closer to a HypercompetentSidekick.
* BurnTheWitch: In the series, people who are suspected of being witches are either burnt at the stake or beheaded.
** In "The Mark of Nimueh", Gwen is falsely accused of witchcraft, and has to be saved by the other characters.
** "The Witchfinder", where Gaius is almost burnt at the stake.
** In "Queen Of Hearts" Merlin escapes being burned at the stake when disguised as an old wizard using magic (it makes you wonder why more don't do that, or can't).
* ButForMeItWasTuesday: When Alvarr confronts Uther, he believes this is the culmination of years of a major vendetta, revenge for Uther ordering the deaths of Alvarr's parents and battling against his regime. He's thrown when Uther reveals that Alvarr was just another sorcerer to him and barely remembers that past crime as part of his purge of magic.
* ButtMonkey: Merlin, especially when "helping" Arthur with his training exercises.
** Morgana [[spoiler:Pendragon]] as well. Even before [[spoiler:her FaceHeelTurn]], the writers did not seem to like her.
* BuxomBeautyStandard: Gwen is quite well-endowed and her outfits draw more and more attention to this as the series progresses.
* CallBack: In the pilot episode Merlin says of Arthur: "I said you were a prat, I just didn't know you were a royal one." In the final episode of the first series, on saying goodbye to Arthur, they have the following exchange:
-->'''Arthur:''' ''You know, sometimes I don't think you know who I am.''\\
'''Merlin:''' ''Oh, I know who you are. You're a prat. And a royal one.''
** Arthur and Gwen's conversation at the end of 3X10 is filled with allusions to the one they had at the conclusion of 2X02; particularly repetition of the words: "when you/I am King, things will be different."
** In 2x04, Merlin tells Arthur that everyone can see his feelings for Gwen and that even a "blind man could see it." Morgana repeats a similar line to Arthur in 3x10.
** Merlin giving Morgana flowers in 2x03 and later in a [[https://www.youtube.com/watch?v=J3PiFk0rM_U deleted scene]] in 3x01.
** Merlin's conversation with Morgana in 3x07:
--->'''Morgana:''' Why are you telling me this?\\
'''Merlin:''' Because I don't understand why anyone would want to hurt their friends.\\
'''Morgana:''' No, you just ''[[spoiler:poison them.]]''
** In 1x13, Morgana pulls Merlin behind a pillar to warn him about Arthur being in danger. In 3x02, Morgana pulls Merlin behind a pillar once more, [[spoiler:but only to threaten him not expose her villainy by reminding that Uther would have him executed if ''she'' revealed to him that Merlin poisoned her.]]
** In 2x12, Morgana recalls to Morgause her assassination attempt on Uther in 1x12.
** Merlin and Arthur's conversation on horse in 4x01 alludes to 2x01:
--->'''Arthur''': Yes, that you're a clotpole.\\
'''Merlin''': That's my word.
** In 4x05, Queen Annis says with almost reluctant admiration "There is something about you, Arthur Pendragon..." which seems very reminiscent of something Arthur himself to Merlin in 1x01.
*** On the same note, Arthur's line in 1x01 was "There's something about you, Merlin." Perhaps coincidentally, Gwen delivers the exact same line to Merlin in 4x08.
** The scene where [[spoiler:Gwen sentences her servant to death]] mirrors the scene where Gwen is dragged before Uther.
** At the end of 3x02, Uther presents Morgana to the court as the person who turned the tide of the battle and saved Camelot, causing everyone present to applaud her bravery. Morgana was, of course, the traitor who initiated the whole thing. Episode 5x07 ends with Arthur congratulating Gwen for rooting out the traitor who had been trying to kill him (she was, of course, the traitor.) The episode ends with the court cheering "Long live the Queen!"
** In 2x13, Arthur advises Merlin with "No man is worth your tears", to which Merlin replies "You're certainly not". In the GrandFinale, Merlin breaks down when [[spoiler: Arthur is dying and Arthur tries to calm him.]]
** The beginning of 5x03 mirrors 1x07 and shows the CharacterDevelopment both Arthur and Merlin have undergone. Both episodes open with Arthur and Merlin hunting, and Merlin being disruptive and scaring off game. Whereas Arthur loses his temper at Merlin in 1x07, shouting at him and hitting him, in 5x03 he just teases Merlin lightly. In both episodes, their hunt is interrupted by a woman's screams, which shows Merlin's HeroicFatigue by the latter episode when he groans at having to investigate it instead of tearing after Arthur like he had in 1x07.
[[/folder]]

[[folder:C]]
* CameBackWrong: [[spoiler: Lancelot]], thanks to Morgana.
* CampfireCharacterExploration: Happened quite a few times while the characters were on quests:
** In "The Sins of the Father", Arthur and Merlin end up bonding over growing up without one of their parents over a campfire (though, in an odd example, they are making the fire during the day rather than at night).
** In "The Eye of the Phoenix", when Merlin reunites with Gwaine in order to save Arthur in the Perilous Lands, Merlin asks Gwaine over the campfire that night why he agreed to come on such a dangerous journey.
-->'''Gwaine''': Same reason as you: Help a friend.\\
'''Merlin''': Arthur's lucky to have us.\\
'''Gwaine''': ''([[HeldGaze looks at Merlin]])'' Not Arthur.
** In "The Diamond of the Day (Part 2)", [[spoiler: Merlin finally reveals his magic to Arthur ''using'' a campfire. The fact that Arthur later encourages him to use magic to light a fire, after initially reacting poorly to reveal, shows how far Arthur has come to accepting Merlin in a short span of time.]]
* CanonCharacterAllAlong: In "The Beginning of the End", Merlin, Morgana, and Arthur help rescue a young druid boy, whom Kilgharrah predicts will kill Arthur. But it isn't until the end of the episode that the boy's name is revealed: [[spoiler: ''Mordred'']].
* CardboardPrison: Not only Camelot's dungeons, but also its "impregnable" vaults.
* CassandraTruth: Merlin lives this trope. In every season and most episodes therein, Merlin usually has foreknowledge of the (dis)loyalties of basically everyone. But he can't ever ''prove'' this because it variously involves a) exposing himself as a wizard, b) selling out someone he would rather not, or c) being pitted against someone who Uther and/or Arthur trust implicitly. You would think, considering everything Merlin says turns out to be true, people might just start giving him the benefit of the doubt.
** More conventionally, there's one instance of Merlin bursting into the throne room and insisting he's a wizard.
** Surprisingly, [[spoiler:Arthur finally catches on to this in the season 4 finale. He realizes that Merlin knew, and has always known, about such betrayals. Arthur, meanwhile, always sees the best in people right up until they stab him in the back. He finds it quite frustrating that the people he treats as friends are so willing to betray him. He predictably reacts quite badly to Merlin's confession of having magic at first.]]
** Also obviously Morgana [[spoiler: due to her powers as a seer]] which ultimately are often ignored especially by [[spoiler: Arthur]] who [[spoiler: frequently dismisses them as nightmares or taking it as a sign of romantic attraction that she dreams about him (this is entirely shippers choice although it does seem to be rather obvious in season 1!)]] This is subverted by the fact that Gauis and Merlin often [[spoiler: use these dreams to their own advantage to help Merlin protect Arthur-often without telling her and again almost always attempting to brush it off as just a dream]]
* CastFullOfPrettyBoys: King Arthur and all of the Knights at The Round Table are all resident {{Hunk}}'s. It also helps that the titular character (Merlin himself) of the series is a real PrettyBoy.
* CastingGag: [[Series/BuffyTheVampireSlayer Giles the ex-black sorcerer outlaws sorcery entirely.]]
* CatapultNightmare: Despite suffering from at least one nightmare per episode, Morgana has surprisingly few of these. However, most recently she flung herself upright from a dream about Gwen becoming Queen of Camelot. She later does this when Agravaine bursts into her hut in Series 4, though, she's not waking from a nightmare, she's just scared.
* CatchPhrase: Arthur's "Shut up, Merlin." You can thank Merlin's MotorMouth for that.
* CentralTheme: BecauseDestinySaysSo and YouCantFightFate.
** The CentralTheme of Series 4 is ThePowerOfTrust.
* Myth/CelticMythology: Season 4 begins on Samhain, [[TruthInTelevision traditionally held as the time when the veil between our world and that of the spirits is at its thinnest]]. It's a night of remembrance for the dead, and a time to take stock and prepare for the coming winter. The [[BloodMagic blood sacrifices]], not so much.
* ChangedMyMindKid: In ''[[Recap/MerlinS01E10TheMomentOfTruth The Moment of Truth]]'', Will refuses to fight against Kanen's men, but he pulls this off in time to save Merlin.
** In ''[[Recap/MerlinS02E13TheLastDragonlord The Last Dragonlord]]'', Balinor refuses to help Camelot initially due to his legitimate grudge against Uther, but changes his mind.
* ChangelingTale: Unsurprisingly, "The Changeling", even though they tweak the traditional definition of what a changeling is.
* CharacterTitle: ''Merlin'', obviously, but also episodes themselves such as ''Lancelot'' and ''Gwaine.''
* CharacterizationMarchesOn: Before becoming something of a regular in the third series, EnsembleDarkHorse Sir Leon had a few scenes in the second. One of his first appearances involves him violently tearing apart Gaius's study in the search for evidence of magic. The sight of him smashing bottles and ripping down tapestries is completely at odds with the gentler character of later episodes, who is also on good enough terms with Gaius (in a DeletedScene) to confide in him that the knights have no confidence in Uther's ability to rule.
* ChronicHeroSyndrome: Merlin.
** He can be excused for it though since most of the people he is trying to save will soon be burnt at a stake.
** Arthur, too.
* ChekhovsGun: The vial of water from Avalon's lake.
** The as-yet unnamed Excalibur.
* ChekhovsGunman: The fact that Freya was cremated on the waters of the same lake that Merlin threw Excalibur into seems mightily suggestive.
** [[spoiler: In "The Coming Of Arthur Part 2" she is pretty much confirmed to be the Lady of the Lake.]]
* {{Chickification}}: Gwen in series two, later in season three she's regaining her reputation as a BadassNormal ([[spoiler:fending off an intruder with a poker, joining the men on their rescue mission, lighting a fire when Arthur cannot]]), whilst still remaining within the boundaries of what a slight young woman would realistically be capable of.
--> '''Gwen''': I ''am'' the blacksmith's daughter, remember?
** But still reverts to "StayInTheKitchen and make bandages" for the series finale, and whilst season four has her defending Merlin from an enemy and having a sword fight with [[spoiler:Morgana]], season five has her playing this trope fully.
* ChildMage: Mordred, Merlin counts also, since out of the six main characters, he is the youngest. All mages in the series were once this if they had innate gifts. Merlin could use his magic before he could talk, and Gaius also mentions in an episode that Morgana had prophetic dreams as a little girl.
* ChildhoodFriends: Merlin and Will.
* ChildrenAreInnocent: Initially played straight with Mordred, who despite being supposedly destined for evil, is at first just an ordinary (if telepathic) little boy. His morality becomes more and more ambiguous with each subsequent appearance, as Uther's persecution drives him to become more and more vengeful. Although he is defending himself against adults, it's still pretty scary for a kid who was raised by an extremely pacifistic people to kill without remorse.
* TheChosenMany: There are actually several. Arthur is the One and Future King, destined to unite Albion and bring back magic, while Merlin is Emrys, destined to protect Arthur so he can complete his destiny. Meanwhile Mordred is destined to one day kill Arthur according to the Great Dragon and in Series 5 is confirmed that the Druids are aware that one of their own is meant to kill Arthur. Guinevere meanwhile also seems to be a chosen one of sorts by being the future queen, with [[spoiler:the GrandFinale implying that through a ProphecyTwist she's the one who brings magic back]] and it's later stated that Morgana is destined to bring back the Old Religion [[spoiler:which turns out to be false since she dies before doing that]].
* TheChosenZero: Merlin's immediate reaction to being told that Arthur is the destined King who will save the land is "There must be another Arthur, because this one's an idiot!"
* ChuckCunninghamSyndrome: Geoffrey of Monmouth.
* CityOfAdventure: Camelot.
* ClapYourHandsIfYouBelieve: When Arthur is [[spoiler:trying to draw Excalibur]], Merlin says that he needs to truly believe he can in order to do it. Subverted since Merlin was just trying to boost Arthur's confidence: once Arthur is sold on Merlin's story, Merlin covertly uses magic to make the task extremely easy for Arthur, thus reinforcing the idea he was trying to instill.
* ClosetShuffle: In Camelot, cabinets are not meant for storage. They're meant as convenient hiding places for Merlin.
* ClothingDamage: Nimueh must have been dragged through a hedge at some point as the bottom half of her dress is ripped in a way that exposes Michelle Ryan's legs. Well, she ''has'' been living in a cave for twenty years!
** Also Freya's dress, but it can be explained since she's been Halig's prisoner for who-knows-how-long.
* CloudCuckooLander: Uther, after being rescued from Morgana's first takeover of Camelot.
* ColourCodedForYourConvenience: Merlin and Arthur usually wear blue and red respectively, as a near-literal example of RedOniBlueOni. RebelliousPrincess Morgana wears bright, jewel-like colours such as reds, blues, purples, and greens, whilst the gentler ShrinkingViolet Guinevere wears almost every shade of pastel imaginable: lavender, peach, pink, and light blue. By series four, the bad guys (Morgana, Agravaine, Helios, and [[spoiler: Shade!Lancelot]]) wear black, whilst those with magical powers are usually delineated by the colour green, particularly Mordred and the other Druids, who wear green cloaks.
* CrystalBall: Not "balls", but there have been at least three examples of crystals that show the future: Morgause's crystal, the Crystal of Neahtid, and the Crystal Cave.
* CoconutSuperpowers: Merlin's ability to slow down time.
** And the shapeshifting magic used by the bad guys in "Gwaine."
* CombatPragmatist: Merlin repeatedly uses magic to gain an advantage by turning the things around him against his opponent.
* ComeOutComeOutWhereverYouAre: Said word-for-word by baddie Kanen in ''[[Recap/MerlinS01E10TheMomentOfTruth The Moment of Truth]]''.
* ComfortingComforter: A variation of this at the end of series two. When all of Camelot is put under a sleeping spell, Arthur picks up Guinevere from the floor and places her on a bed.
* ComicallyMissingThePoint: The show does this quite often, particularly with Merlin himself.
-->'''Arthur:''' You can't leave him here [on the floor]! We have to get him onto the bed.\\
'''Merlin:''' Why? He's asleep. He's not going to know.\\
'''Arthur:''' Merlin!\\
'''Merlin:''' Alright, I'll get him a pillow.\\
'''Arthur:''' He's ''the king!''\\
'''Merlin:''' You're right....''two pillows!''
* [[CompositeCharacter Composite Object]]: As with many modern retellings, Excalibur is combined with the Sword in the Stone (the oldest versions of the tale describe them as two very distinct swords - when Arthur breaks the latter in battle, he gains the former from the Lady of the Lake).
* ConflictingLoyalty: Merlin, most especially in series 2. His destiny is clearly to stand by Arthur, but Arthur's views on magic, even if only impressed upon him by Uther, can make for some not inconsiderable moral tension. ''The Sins of The Father'' showcases this dilemma to particularly heart-breaking effect.
** Morgana to some degree as well regarding Uther and his ruthlessness towards magic. Made all the worse when she finds out [[spoiler:that she's a seer and has magic herself]]
** Arthur also has moments where he butts heads with Uther, usually when the latter is being too harsh, accusing an obviously innocent person of witchcraft, or not taking good enough care of the people of Camelot.
* ConspicuousGloves: Uther, who never took them off.
* ContinuityNod: In ''The Castle of Fyrien'', Morgana pointedly refuses to let Merlin pour her a drink.
** In ''The Darkest Hour'' Part 2, Arthur leads his knights back to the cave of the Wildrynn and tells them to smear themselves in berries to mask their scent.
* CoolChair: The throne(s) of Camelot.
* CoolOldGuy: Gaius.
* CoolSword: [[{{Excalibur}} The most iconic ever.]]
* CoolVersusAwesome: Immortal undead soldiers versus the Knights of the Round Table.
* CostumePorn: Morgana's entire wardrobe, including dresses that wouldn't look too out of place at a cocktail party, as well as the gowns of various ladies and princesses that turn up throughout the series and Guinevere's [[spoiler:[[http://oi52.tinypic.com/1055w5c.jpg coronation gown]]]]. [[http://24.media.tumblr.com/fbb6b879859cfb6bde093c16b63c6f6a/tumblr_mfrospBtOC1qlp5jzo1_500.jpg The decoration on Arthur's armor]] is remarkably intricate although it won't show unless in close-up.
* CradlingYourKill: Merlin with [[spoiler: Morgana's body in 2x12.]] He also holds [[spoiler: Morgana]] as she's dying in the series finale.
* CrazyJealousGuy: Arthur in 4x09 when he [[spoiler: when he walks in on Gwen and Lancelot making out. His first instinct is to [[MurderTheHypotenuse try and kill the guy who had been one of his most loyal knights]] and had shown him mercy in the tournament earlier. And then by the end of the episode, he banishes Gwen from Camelot.]]
** Merlin can be this at times as well. He demonstrates jealousy toward anyone who poses a threat to his relationship with Arthur, such as Cedric and Princess Mithian, and is willing to share Arthur with only [[PlatonicLifePartners one other person in the world]]: Guinevere, who happens to be his own very close friend.
* CrazyPrepared: Myror just ''happened'' to be carrying a retractable, needle-tipped lance along with him.
** If the spell translations are to be believed (hinges on WordOfGod here), Merlin is too. Half the spells are so tailored to the situation that either he's making them up as he goes or he really does learn spells ''just in case'' he wants a magnetic sword, he needs to drop bed covers on someone, or he needs to throw a bench.
* CreepyChild: Mordred. Also, a hallucination Uther suffers at the beginning of Series 3.
** The ghost child from ''A Herald of a New Age'' that possesses Elyan.
* CrouchingMoronHiddenBadass: Merlin may appear to be a clumsy, idiotic servant, but once his magic unleashes on you, you better run.
* CurseCutShort: Watch Arthur carefully when Uther tells him that Elena is his prospective bride. He clearly mouths: "What the f...?"
* TheCutie: Freya. She's highly endearing.
* CutHisHeartOutWithASpoon: Non-lethal version. In "The Death Song of Uther Pendragon", Arthur warns Merlin to keep quiet about the spirit-summoning horn he intends to use. Merlin points out that Arthur is making said threat while holding a spoon. Cut to outside the room, and Merlin suddenly shouts in pain.
* CycleOfRevenge: A CentralTheme.
[[/folder]]