Alvarr is determined to allow magic to be used gain and destroy Camelot. Alvarr needs to reclaim the Crystal of Neahtid to make his plan work. Alvarr and Morgana try to get their hands on the crystal and use a druid boy to help them. Merlin is surprised when he finds out the real power of the crystal.
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 .