Fatal Cargo - S4-E7
Revealing mistake: The seam on the back of the gorilla costume is visible as he attacks the doctor's campsite.
Voyage to the Bottom of the Sea (1964)
1 revealing mistake in season 4 - chronological order
Starring: Richard Basehart, David Hedison, Del Monroe, Robert Dowdell
Continuity mistake: During the battle a railing on a pirate ship falls off, only to be seen in the next shot intact, then missing in a subsequent shot.