Camelot faces a new golden age, but even as the city flowers, the dark seeds of destruction are being sown. In the frozen wastelands of the north, men are disappearing without a trace. King Arthur and his knights undertake a dangerous mission into the unknown in search of answers - but once there, Merlin finds himself locked in a battle unlike any he has fought before.
Quest roles:
Eoin Macken(Gwaine), Tom Hopper(Sir Percival), Lindsay Duncan(Queen Annis), Sophie Rundle(Sefa), Liam Cunningham(Ruadan), Julian Glover(Lochru), Stephen McCole(Ragnor), Alexander Vlahos(Mordred), John Bradley(Tyr Seward)