List of Merlin characters
Agravaine kept his cover as a seemingly loyal kinsman to Arthur until the penultimate episode, "The Sword and the Stone, Part One," when he cleared the way for Morgana and the warlord, Helios, to invade Camelot, even joining in the fighting during the battle.
The episode "The Hollow Queen" also reveals that as Aithusa grew while imprisoned by Sarrum, the pit she and Morgana were housed in became too small for the growing dragon, and it caused her to become deformed, twisted, and stunted in her growth.
Aithusa seems to be based on the white dragon that represented the Saxons in Arthurian legend and is noticeably small compared to Kilgarragh, only being as large as a wyvern at around 6 or 7 feet long.
However, when the Great Purge began, Gaius was forced to help Alice flee Camelot by striking her name from Uther's lists and remaining behind to avoid drawing attention to his role in her escape.
Annis is ultimately a very just and fair woman, but also spontaneous and extreme in her actions, forgiving Arthur his misjudgment and homicide unusually quickly, withdrawing her army and restoring the peace contract that Uther originally signed with her father-in-law and refusing to cooperate further with Morgana.
In the first episode, "The Darkest Hour, Part One," Arthur found Camelot under threat when Morgana sacrificed a dying Morgause to release the Dorocha, the spirits of the dead, to wreak her revenge on the kingdom.
Bayard's army was dispatched to begin a war with Camelot, but the crisis was averted when Gaius revealed to Uther that the poisoned cup had actually been planted by Nimueh, who hoped to foment trouble for the kingdom.
Upon learning that the troll was an imposter, Gaius and Merlin attempted to get rid of her, but were unable to stop her from marrying Uther and having herself crowned Queen of Camelot at the conclusion of "Beauty and the Beast, Part One".
In "Beauty and the Beast, Part Two", the fake Catrina utilised the enchantment she held over Uther even further, creating a rift between him and Arthur and even persuading him to disinherit his son and leave her as next in line for the throne.
In the second-season premiere, "The Curse of Cornelius Sigan", Cedric sought to gain access to Arthur's personal rooms in order to steal the keys to an underground burial chamber where a great treasure had been discovered.
Seeking Arthur's location, Morgana tortured Elyan with a Nathair snake, which caused him "pain beyond all imagining" and, according to Gaius, stresses the body to the full extent of human endurance.
Even without magic, Gaius has shown exceptional talent as a physician, regularly treating injuries in the court, and even preparing a draught that precisely duplicates the taste of a troll potion without any access to the original recipe.
However, when a sickness renders Camelot asleep in the face of an attack by the deadly Knights of Medhir, the dragon forces Merlin's hand by demanding he honour his promise in exchange for knowledge.
Guinevere ("Gwen"; portrayed by Angel Coulby) enters the story as Lady Morgana's personal servant, eventually falling in love with and marrying King Arthur, thus becoming Queen of Camelot.
Lady Helen of Mora (portrayed by Eve Myles) was a famous singer who was on her way to Camelot to perform at King Uther's festival, until she was possessed and killed by Mary Collins using poppet magic.
Collins then assumed Lady Helen's appearance, also serving as a romantic interest to King Uther Pendragon, in an attempt to kill Prince Arthur, but Merlin saves his life by using magic and becomes his manservant.
In the aftermath of the battle, Uther reluctantly considered restoring Lancelot's knighthood, but the man refused the honour, since he did not wish to take full credit for destroying the griffin when Merlin's contribution was so critical.
In the third series finale, The Coming of Arthur, Part Two, the two men travelled to Camelot when Lancelot received a message from Merlin, requesting aid following Morgana and Morgause's takeover of the kingdom with an army of immortal soldiers.
In the ensuing battle to retake Camelot, Lancelot accompanied Merlin when the warlock set off to empty the Cup of Life of the blood that made Morgana and Morgause's army immortal.
The series focuses on his relationship with Arthur, which is comically portrayed with the prince always rudely teasing Merlin, who avoids suspicion of his powers by appearing dim-witted, which is aided by occasional genuine clumsiness.
Over time, sadly, her growing fear that she has magic, as well as her increasing anger towards Uther's callousness, a distance from Arthur (possibly due to his growing close to her maid), the hostility of the Great Dragon toward her (that she is unaware of) and most importantly, the unwillingness of Merlin and Gaius to tell her the truth or give her any real help in understanding or controlling what's happening to her – all of which serves to leave her feeling increasingly isolated and alone- which enables Morgause and others to corrupt and use her – eventually; following a long period of isolation with Morgause (indicated to be about a year) sees her previous compassionate views warped and Morgana become fully committed to evil.
Though Gaius realises that the sleeping potions (in reality, they were also attempts to keep her burgeoning powers latent) are no longer working, but he stubbornly refuses to acknowledge what's happening to Morgana, and patently ignores Merlin's pleas to try and help her.
Merlin later saves Gaius and himself from Aredian's charges, by making the Witchfinder appear a fraud: he dies attempting to escape an accusation of sorcery himself- and having taken Morgana hostage, he immediately loses Uther's favour and trust.
However, her plan was more complex, for she spares him- but requires him to travel to her domain and face another challenge, at a later date (which he accepts, despite Uther's adamant refusal); she also implies she knew his mother, the late Ygraine- which only serves to make Arthur more willing to seek her out again.
When Agravaine visits Morgana to inform her of her success in Uther's demise, she is evidently disturbed, if not saddened, by her father's death, and claims that there will be no celebrations until she takes the throne of Camelot.
Morgana orders Agravaine to lead her men to Ealdor whilst she enjoys her time on the throne, burning down the people's crops when they refuse to declare their allegiance to the dark queen.
While Morgana was furious over this revelation and wished to exact revenge against Uther for decades of lies, Morgause preferred to consider the long-term ramifications of this information and urged her sister not to do anything rash.
It is suggested that Nimueh's beautiful features are an illusion brought about by her powerful magic; she can change her appearance at will ("The Poison Chalice"), looking no older than the 21-year-old Arthur despite having been in service to his family long before his birth.
He died while fighting the mysterious "Black Knight", who was in fact the reanimated form of Uther Pendragon's late brother-in-law Tristan De Bois, brought back as an immortal wraith by Nimueh's magic.
The young king ends up very disappointed by the reunion; Uther disagrees with almost all of the changes Arthur has made, including the knighting of common-born men, the very idea of the Round Table and crowning Guinevere queen.
