Avon (Paul Darrow) agrees to trade the ship's computer, Orac, for a new, highly destructive long-range weapon, the tachyon funnel. Unfortunately, the inventor of the weapon, a megalomaniac recluse named Egrorian (John Savident) double-crosses Avon and sabotages the Scorpio crew's space shuttle. The lives of the space travelers are dependent upon Vila (Michael Keating), who may have to jettison himself into space to allow his comrades to escape their latest predicament. "Orbit" was first telecast on December 7, 1981. ~ Hal Erickson, Rovi