The four-part Doctor Who adventure "Mawdryn Undead" begins on a seemingly arbitrary note, as a pair of juvenile delinquents go for a joyride in the Brigadier's vintage automobile. After the inevitable crash, one of the boys, actually a space alien named Vizlor Turlough (Mark Strickson), is recruited for a daunting assignment. The recruiter is the Black Guardian (Valentine Dyall); the assignment is to kill the Black Guardian's sworn enemy -- the Doctor (Peter Davison). Originally telecast on February 1, 1983, "Mawdryn Undead, Episode 1" was written by Peter Grimwade. ~ Hal Erickson, All Movie Guide