Character mistake: When Adams is chewing out Altaira for flirting with his crew, he says that he is "in command of 18 perfect physical specimens." With him, that would make for a total crew of 19 on the C57-D. But the complete cast only shows 18 names, including Walter Pidgeon as Morbius and Anne Francis as Alta. (And discounting Robby and his human handlers). Thus it would seem Adams is off by three. He has only 15 under his command. I've tried counting them when they're in group shots, but can't see everyone.
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Character mistake: When Henry Fonda is led to his cell, shot in a prison in Queens, a real inmate yells "What'd they get ya for, Henry?"