Plot hole: Patrick McGoohan shoots the marine captain thinking him to be the traitor, thus, McGoohan believes, stopping the marine killing Ernest Borgnine. But shortly afterwards McGoohan comes out of the hut and addresses Borgnine sarcastically as 'Comrade'. How did he know he was the real traitor? Nothing has yet happened that should cause him to see this truth.
Ice Station Zebra (1968)
1 plot hole
Directed by: John Sturges
Starring: Ernest Borgnine, Rock Hudson, Patrick McGoohan, Jim Brown
Character mistake: The crew many times refers to the sub as a ship - subs are always called a boat.
Cmdr. Ferraday: We operate on a first-name basis. My first name is Captain.
Trivia: The submarine used in the movie as a (supposed) nuclear submarine was the U.S.S. Ronquil (SS-396), a WWII Balao-class diesel-electric submarine that had received a GUPPY IIA conversion. The number painted on the sail (509) was selected because it was from a block of hull numbers canceled at the end of WWII and never used.