Previously believed to have been called The Tribe, the episode will air at 8.05pm on Saturday 10th November on BBC One, and will guest-star Kelly Wenham as Queen Mab.
When Gwen is snatched from Camelot without warning, Merlin knows there can be only one person responsible: Morgana. Arthur is determined to rescue his Queen, but it will not be easy, for she is locked in the Dark Tower, a place that haunts the dreams of men. Arthur and his Knights must embark on a quest like no other, battling through a landscape riddled with hidden dangers, perilous obstacles, and magical beings. As they near their goal, Merlin's sense of dread reaches breaking point. What twisted game is Morgana playing? And more importantly, just what is the final test that awaits them in the tower?