Revealing mistake: The injured Spain falls and tries to crawl away from the alien, leaving handprints in the dust on the floor. Just to his left, you can see several handprints already on the floor from previous takes. (00:47:30)
The Outer Limits (1963)
1 revealing mistake in The Invisibles - chronological order
Continuity mistake: In the lab, the alien's arms change positions instantaneously between shots. (00:13:50)
Dr. Paul Wayne: So what difference does it make, whether it's 20 minutes or 20 years, since neither amounts to the faintest echo of the tiniest whisper in the thunder of time.
The Forms of Things Unknown - S1-E32
Trivia: This is the only Outer Limits episode that lacks both opening and closing narration. It was absent because "Forms" was the unsold pilot for a series called The Unknown. A second version, stripped of all its supernatural elements (Tone was simply a mad scientist, not a real time traveler), also failed to sell.