Continuity: Despite the explicit dialogue and written appearances of the name that make it clear that the character Scott ffolliott has no capital F, the name still appears as Ffolliott in the end credit cast list.
Continuity: Window shadow on Johnny's jacket changes while in his boss's office.
Continuity: Johnny's raincoat lapel is folded, then flat, then folded while on the steps in the rain.
Continuity: The ladder appears and disappears beside the windmill door.
Continuity: The taxi rear window view shows that they drive up the same street twice.
Miscellaneous: The film is reversed left-to-right during the chess game at the police station.
Crew or equipment visible: During the plane crash climax, during the montage of images after the plane hits the water, the camera tilts too high up and the lights of the set can be seen.
Revealing mistakes: As the arguing couple depart the elevator at the top of the cathedral tower, its walls can be seen to shake hugely.
Revealing mistakes: When ffolliott returns with backup to find van Meer unconscious on the bed, and the room deserted, the doorframe shakes noticeably as the actors pass through it.
Revealing mistakes: As the Purser on the ship tells John and Carol that he has no more cabins, the right side of his fake moustache can be seen sliding down. He surreptitiously pushes back in place, but as they turn back for a second try and he continues speaking, the moustache slides down again.
Continuity: When Johnny and Carol step down from the taxi in front of her house, he takes the suitcase with her left hand and changes it to the right one, to direct her with the left hand. After the taxi leaves, he is holding the suitcase in his left hand.
Continuity: In Fisher's office, Scott picks up a cigarette from the cigarette case and puts it in his mouth. The following shot shows him smoking, without apparently lighting the cigarette at all.
Audio/visual unsynchronized: After the crash, as the survivors spot the American ship steaming toward them, the matte line between the moving water and the sky can easily be seen.
Revealing mistakes: During the scene where the passengers are scrambling to get out of the sinking Clipper, a man grabs a suitcase and smashes a window, leaving a lot of large, jagged pieces of glass in the frame. He then climbs through the window and sits directly on the jagged glass.
Crew or equipment visible: The streetcars are obvious dummies running on rubber tires.
Continuity: The hair of Carol Fisher is wet after she completely submerges next to ffolliott after the plane crash. In the exact next shot her hair is nearly dry again.
Continuity: In the chase scene at the windmill site the aircraft circling is in one scene a twin-engined, twin-tailed low wing type, and in a subsequent scene it suddenly becomes a single engined, single tailed high wing aircraft.
Continuity: In the scene where Jones and his new "body guard" are in the car, the body guard is on the audiences right, Jones on the left. When they get out of the car, from the left, the body guard gets out first.
Crew or equipment visible: When Jones and Rowley (Edmund Gwenn) get in the taxi a crouched crew member is reflected in the side window as the cab pulls away.