Factual error: The giant squid's tentacles aren't shaped like ones in the real world are.
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During the "Whale of a Tail" scene, there are several instances when Kirk Douglas' hands are away from the guitar strings, to ring the bell or twirl the guitar, yet the sound of the guitar strumming continues without missing a beat. See more...
20,000 Leagues Under the Sea mistakes
Revealing: In the scene near the end when water is filling up the submarine, Kirk Douglas begins fighting with a member of the crew to escape. As Douglas hits him his false sideburn falls off and flies across the screen.
Audio problem: During the "Whale of a Tail" scene, there are several instances when Kirk Douglas' hands are away from the guitar strings, to ring the bell or twirl the guitar, yet the sound of the guitar strumming continues without missing a beat.