The Great Dragon is finally free. Full of rage, he attacks Camelot with pitiless intensity. The castle is crumbling and Arthur's men cannot hold out much longer but only a Dragonlord can kill a dragon and Uther wiped them all out years ago. Or did he? Gaius admits one such man could still be alive and in hiding.
The last Dragonlord is the key to Merlin's own past as well as the future of Camelot, but will Arthur and Merlin find Balinor in time to save the kingdom?
Starring: Colin Morgan (Merlin), Angel Coulby (Gwen), Bradley James (Arthur Pendragon), Katie McGrath (Morgana), Anthony Head (Uther Pendragon), Richard Wilson (Gaius), John Hurt (Voice of the Great Dragon)
Guest Starring: John Lynch (Balinor), Rupert Young (Sir Leon), Jonathan Coyne (Asgerd), Alexander Delamere (Innkeeper)
Written by Julian Jones
Directed by Jeremy Webb
Trivia: Although Katie McGrath is credited in the opening titles, Morgana does not appear in this episode. At the May 2010 London Expo Press Conference, executive producer Johnny Capps revealed the original ending of the episode had Merlin and Arthur finding Morgana in the council chambers.