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?
Elenco: Colin Morgan , Bradley James , Angel Coulby , Katie McGrath , John Hurt , Richard Wilson , Eoin Macken , Katie McGrath , Richard Wilson , Rupert Young , Santiago Cabrera , Tom Hopper .