Other mistake: After Malloy shoots himself his hand does not drop the gun onto the table. Instead, his hand places the gun on the table then his fingers gently shoves the gun out of his hand.
Continuity mistake: The shots of Doran from his left rear shows him a couple feet away from the wall while frontal shots show him backed up against the wall.
Rod Serling: For those of you who've never met me, you might call me the under-nourished Alfred Hitchcock.
Trivia: The scene of the spooky castle on the rocky shore was used in episodes of "Gilligan's Island" featuring Vito Scotti as mad scientist Boris Balinkoff.