In the conclusion of the four-part story "The Mask of Mandragora," both the Doctor (Tom Baker) and Sarah (Elisabeth Sladen) are slated to die at the hands of the Renaissance-era religious coven, The Brotherhood of Demnos. Arriving in the Brotherhood's palace, the Doctor steels himself for a showdown with coven leader Hieronymous (Norman Jones) -- while the Mandragora Helix, which has been using Hieronymous as a pawn in a scheme to take over the world, awaits the outcome of this final battle. An omnimous warning caps the last scene of "The Mask of Mandragora, Episode 4," which was written by Terrance Dicks and first aired on September 25, 1976. ~ Hal Erickson, All Movie Guide