Goofs

When Brian Younger is walking by Kit Preston's building, he hears the door to the construction site squeaking loudly as it opens and shuts. A second later he goes through it, and the door makes no sound at all.

When Tony and Aunt Bea are talking at dinner while Kit and Charles are dancing, the position of Bea's green dress on her shoulders and arms changes a few times between shots.

Even in 1960, no construction company would allow pedestrians to walk beneath a 5,000 lb. steel beam as it is being hoisted.

Malcolm says that his mother, a servant, will have trouble paying the doctor's bills. By this time, medical care in the UK had been free for 12 years. There were still private doctors who were paid by the user, but they treated the rich.

The "London" bus in the film may be a red double-Decker and is meant to be a 1939 RT type but looks nothing like a real one. This is explained by Day' s scenes being filmed in the studio and doubles used for London exterior scenes.

When Kitt Preston exits the shop after ordering the luggage, she is shown exiting from a shop was below ground. These shops with an entrance below ground did not exist in the fashionable areas of London, but this was clearly a backlot set on the Universal Studios lot.

Early in the film when the foreman is taken to task for the steel beam falling, he is wearing a circular hard hat with a brim all the way round. These were never used in the UK.

Rex Harrison leaves the flat as a "decoy" for his wife's stalker, but he enters his car on the left side and the car's steering wheel is also on the left side. If it were a British car, he would have entered it on the right side, but it is a late-'50s Ferrari 250 GT, which was only made with left-hand steering, but could still be owned and driven by an Englishman.

At the beginning of the film, a lot of the London "pea soup" fog is an optical or camera effect as it noticeably moves as the camera moves.

Both the contractor and Malcom call Kit Miss Preston, although both of them clearly know she is married.

During the sequence when Kit receives one of the anonymous phone calls in her bedroom, (just before the mysterious stranger enters her apartment for the first time), a crew member's moving shadow is visible on the left in the shot where she's putting on her shoes to exit the room.

John Gavin attempts a British accent in his scenes in the film, but his attempts at a British accent fail, and his American accent is heard throughout the entire film.

When Nora leaves the apartment for the first time, she mentions to Mrs. Preston that a "cable" came for her. This is an American term. As an English woman, Nora would use the word "telegram".