Friday the 13th: The Series - Season 2 Episode 26 Coven of Darkness

The trio attempt to recover a ""witches' ladder"", a beaded necklace that can greatly enhance a witch's power. It is in the safekeeping of a coven of white witches. Unbeknownst to them, a coven of black witches, led originally be Lewis Vendredi and then by his female lieutenant are also trying to get the ladder. They cast a spell on Ryan, turning him into a mindless slave who brings them the necklace from the Vault. Jack and Micki, tapping into Micki's latent occult powers, manage to break the spell on Ryan, recover the witches' ladder, and destroy the coven.