Voltron: The Third Dimension

Season 1, Episode 10

Episode Title: Descent into Madness

Air Date: 1999-02-06

Overview:

Keith discovers Zarkon is only pretending to be reformed. Before Keith can warn the others, Haggar casts a spell that turns him into a feral beast and makes him forget what he knew. While they don't know what caused it, the rest of the Voltron Force try everything to find a cure.