Continuity mistake: The train that transports The Haynes Sisters and Wallace and Davis from Florida to Vermont is shown as being of the Atchison, Topeka and Santa Fe Railway in one sequence, and of the Southern Pacific Railroad in another. Neither railway ran on the east coast of the U.S.
Continuity mistake: Before Tony leaves he closes the drapes. He then says he won't go out and will stay home. She says to go out, and he agrees, so he goes to the drapes and closes them again.
Other mistake: When they encounter the first ant, the policeman runs out of ammo, but the FBI agent fires at least nine shots. Not bad for a snubnose revolver that holds 5 or 6 rounds.
Factual error: Toshiro Mifune's character, Kikuchiyo, travels to the bandits' camp and steals one of their two remaining fuselock muskets. Shortly afterward, the bandits fire twice at the samurai within five seconds with their last firearm. A fuselock takes as much as two minutes to reload, prime, and fire.
Visible crew/equipment: There is a truck short of Dandridge dancing down the street and there is a spectacular reflection in an angled shop window of the entire camera crew leading the singer.
Continuity mistake: There's an oscillating fan near the ceiling that alternates between running and not running from one cut to another in one scene.
Revealing mistake: When O'Keefe takes his bride-to-be Dolaroo to Hong Kong to be married, a 1950's truck goes past in the background. Unfortunately, the film is set in 1870.
Continuity mistake: In the barn dance scene Gideon is doing flips on the sawhorse. His shirt becomes untucked and then retucked between flips.
Factual error: The giant squid's tentacles aren't shaped like ones in the real world are.
Continuity mistake: When Johnny Friendly is threatening Charlie about keeping Terry from testifying, they are seated at a table across from each other. There is a bottle of alcohol in front of Charlie. In most of the scenes of Charlie behind the bottle, the label can be seen in full. In a couple of scenes, the bottle is turned to the right and only shows a partial label. Charlie was obviously not handling the bottle.
Factual error: There is a shot of a large arena where gladiatorial combats take place. Arranged around the top of the arena are a number of classical statues, one of which is Michelangelo's statue of David circa 1505 AD, 1,465 years too early!
Factual error: In the shot where the three officers ride the aircraft elevator from the hangar deck to the flight deck after arriving aboard the admiral's carrier, you can briefly see some of the aircraft parked on the hangar deck, and they are jet aircraft. The aircraft have pointed noses, no propellers, and the fuselage shape and markings are consistent with first generation Navy carrier jets. These types were not in service until the mid-50s (See "Bridges of Toko-Ri").
Other mistake: In analogy to David's mishap with the champagne glasses old Mr. Larrabee crushes an olive jar when he sits down. However, in contrast to David he puts the jar into the front pocket of his pants, and olive jars don't break even if you sit on them (remember what he did to one when he tried to get the last olive out.). (01:46:55)
Deliberate mistake: After the airplane loses its propeller and descends to lower altitude, the cockpit constantly shakes due to turbulence, and the flight crew complains about it in one scene. However, when the camera switches to the passenger cabin, everything remains perfectly still and serene until the airplane is on its final landing approach near the end of the movie.
Visible crew/equipment: In the opening scene, Edmund O'Brien grabs a bookie, drags him down an alley, and around a corner. When they round the corner, the entire boom and mic cast a huge shadow against a stark white wall.
Continuity mistake: After the operation to change Vic Brady's face, the first time the bandages come off, the scar on his forehead runs diagonal from the top of his nose to well above the eye. However when he's shot by the pool, the scar runs laterally across the middle of his forehead.
Visible crew/equipment: You can see the wires leading from the planes as they attack Gojira.
Continuity mistake: When Richard Denning and Richard Carlson approach the boat ladder coming back from their first dive in the Black Lagoon, you can see the net hanging underwater just to their right. It already has the huge torn hole that is in it when they hoist it up after the creature is caught for a moment in a later scene.
Factual error: After Gene Kelly sings "The Heather on the Hill", he sees more heather on the other side of the bridge. He starts across but Cyd Charisse freezes in horror, since to cross the bridge would break the spell over the village of Brigadoon. She then drops some of her heather in the middle of the path and runs back to the village. The camera cuts to Gene Kelly chasing after her, but the heather dropped on the path has disappeared.
Visible crew/equipment: When the mad King George III hides from Brummel and the prince behind the draperies, the boom shadow makes a prominent appearance on the wall at the top right of the screen.