Synopsis by Hal Erickson
A revolution against the Federation takes place on the planet Albion. Blake (Gareth Thomas) and his crew arrive on the planet in hopes of soliciting the aid of Space Major Provine (Paul Shelley), who supposedly knows the location of the Federation's Central Control. First, however, a powerful bomb must be defused by Avon (Paul Darrow) -- a task complicated by the non-cooperation of Del Grant (Tom Chadbon), the embittered brother of Avon's former lover. "Countdown" was initially telecast on March 6, 1979.