Quick-Quick Slow Death - S4-E19
Revealing mistake: When Mrs. Peel unmasks the recently-murdered Bernard, the corpse's eyelid twitches. (00:37:00)
The Avengers (1961)
1 revealing mistake in Quick-Quick Slow Death - chronological order
Starring: Patrick Macnee
Too Many Christmas Trees - S4-E13
Continuity mistake: When Steed and Emma are driving to the estate, the car's windscreen keeps disappearing. It's there in full shots, gone in close-ups, and reappears again every time we cut back to a long shot. (00:10:30)