Deliberate mistake: Because Stephen Greif tore an Achilles tendon playing squash, a stand-in had to complete his scene with Servalan in Ensor's underground complex. The result was a very odd segment in which we hear Travis' voice (pre-recorded by Greif) answering Servalan's lines, but never see him - except for an awkward shot of shuffling, black-booted feet that are all-too-obviously not Greif's.
Blake's 7 (1978)
1 deliberate mistake in Orac
Starring: Jan Chappell, Michael Keating, Paul Darrow, Peter Tuddenham
Time Squad - S1-E4
Continuity mistake: During Blake's first encounter with Cally, the smudges on the front of his tunic (including a big chalky footprint left by her boot) disappear, reappear and rearrange themselves several times between shots. (00:31:20)
More trivia for Blake's 7