In the conclusion of the four-part story "Four to Doomsday," the Doctor (Peter Davison) discovers that the alien Urbankans intend to wipe out humankind, then repopulate the earth with androids designed to resemble the planet's various ethnic types. Only by hoodwinking the androids into performing a series of frenzied ritualistic dances will the Doctor be able to prevent this cataclysmic disaster. Stratford Johns guest stars as the frog-like Urbankan Monarch. First telecast January 26, 1982, "Four to Doomsday, Episode 4" was written by Terence Dudley. ~ Hal Erickson, Rovi