Morgana and Helios have successfully captured Camelot, and Merlin and Arthur are outlaws on the run. Trapped in Ealdor with a ruthless army closing in, their situation becomes desperate. Arthur must take control before Camelot is lost forever.
But faced with Agravaine's betrayal and the strength of Morgana's force, the young King has lost his conviction. Only Merlin can restore his faith, and only an extraordinary act can prove to the King that he was born to rule. Will the young warlock convince Arthur before his dreams of Albion fall to pieces?
Starring: Colin Morgan (Merlin), Angel Coulby (Gwen), Bradley James (Arthur Pendragon), Katie McGrath (Morgana), Nathaniel Parker (Agravaine), Richard Wilson (Gaius), John Hurt (Voice of the Great Dragon)
Guest Starring: Ben Daniels (Tristan), Miranda Raison (Isolde), Terence Maynard (Helios), Rupert Young (Sir Leon), Eoin Macken (Sir Gwaine), Adetomiwa Edun (Sir Elyan), Tom Hopper (Sir Percival)
Written by Julian Jones
Directed by Alice Troughton