Episode 12 of 13.
First transmission on Saturday November 27, 2010 (UK)
The official details about the episode are as follows…
3.12 The Coming of Arthur Part 1
Merlin and Arthur are sent on a dangerous mission to capture the Cup of Life, a powerful magical artifact that carries the gift of immortality.
But before they can retrieve the Cup, they are captured by unscrupulous slave trader, Jarl. A trusted friend comes to their rescue and they escape, but with Jarl’s help the cup falls into Morgause’s hands. With an immortal army at their disposal, will Morgause and Morgana topple Uther once and for all?
Merlin is played by Colin Morgan, Arthur by Bradley James, Uther Pendragon by Anthony Head, Gaius by Richard Wilson, Morgana by Katie McGrath, Gwen by Angel Coulby and the voice of the Dragon by John Hurt. Emilia Fox guest stars as Morgause, Tom Eliis as Cenred, Ralph Ineson as Jarl and Eoin Macken as Gwaine.