The Radio Times have confirmed that Series 4 of Merlin will begin straight after Doctor Who on Saturday 1st October at 7.50pm on BBC1.

The series kicks off with the first of an epic two-part opener, The Darkest Hour. The episode title was previously rumoured as Revival of the Witch.

Merlin faces his toughest challenge yet when Morgana’s blinkered determination threatens not only Arthur’s future, but also the very balance of the world. With her magic stronger than ever, the sorceress summons the mighty Callieach to tear open the veil between the worlds.