Factual error: While featuring a brand-new 1962 Cadillac, a 1963 Chevrolet and 1963 Ford are shown.
Factual error: Amazon rivers have no high salinity as shown as necessary to maintain the creature.
Audio problem: When Michael Shannon fires his gun, you can hear bullet casings falling to the floor, as is normal with a semi-automatic pistol. However, his gun is a revolver, so the casings won't eject until the gun is opened and emptied manually before reloading. (01:07:10)
Answer: IMDB often has a "connection" section that has some of these trivia facts. "The Story of Ruth" (1960) was playing in the theater. But so far that's the only old movie played that is listed. "Mardi Gras" (1958) was seen on the marquee.
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