Watch the trailer for, ‘Merlin: The Drawing of the Dark’ which airs on the 15th December at 8.15pm to 9.00pm on BBC One.

Mordred finds himself torn between loyalty and love, but little does he realise that the path he chooses will shape Camelot’s destiny… As the drums of war beat ever louder, a desperate Merlin feels trapped by the cruel circle of fate – is he powerless to stop his dreams of Albion from crumbling to dust?