Cary Grant had announced his retirement from acting in February 1953, stating that since the rise of Method actors like Marlon Brando, most people were no longer interested in seeing him. He was also angry at the way Charles Chaplin had been treated by the HUAAC. He was lured out of his retirement to make this movie, and thereafter, continued acting for a further eleven years.
On September 14, 1982, Princess Grace Kelly was killed in an automobile accident in Monaco, supposedly on the same road as her famous chase scene in this movie, and not far from where she had a picnic scene with Cary Grant. She was fifty-two-years-old and lost control of her car after apparently suffering a stroke while at the wheel.
John Robie mentions that as a youth he was in a trapeze group that travelled around Europe. In real-life, Cary Grant was in an acrobatic troupe that toured around Europe (and eventually brought him to America) when he was young.
The lines in the picnic scene, when Francie (Grace Kelly) asks John (Cary Grant), "Do you want a leg or a breast?" and he responds, "You make the choice.", were improvised. The same suggestive dialogue was used by Constance Towers to John Wayne in The Horse Soldiers (1959).
For the scene between Robie and the insurance agent, when they talk about the cook's sensitive hands, the German version of the movie differs completely from the original. In English, Robie notes he once strangled a German general without a sound, while in German, he says he once caught a lion escaped from a circus with his bare hands.
Director Sir Alfred Hitchcock asked if chase scenes could be filmed from a helicopter, which required some ingenuity, as camera mounts did not exist for this purpose at the time. Using a Sikorsky S-51, UK registered G-AJOV, a former BEA airframe, the side door was removed, and the camera jerry-rigged with ropes, wires, and cables. These shots were done in July 1954, according to a "Making of" short documentary included in the DVD release.
There are two references to Sir Alfred Hitchcock's dislike of runny egg yolks. At the beginning, when the restaurant's kitchen staff, his fellow ex-cons and comrades from the French resistance, believe Cary Grant to be responsible for the recent thefts, someone throws a raw egg, which hits the glass and splatters. One of them also offers him a saucer of milk, referring to his former nickname, "the Cat". Later in the movie, Jessie Royce Landis puts out a cigarette in a sunny-side-up egg. On the other hand, when he invites the insurance man (portrayed by John Williams) to lunch, he serves a quiche Lorraine.
In an early shot, a newspaper article called "Europe's Lighter Side" by Art Buchwald speculates on whether "the Cat" is on the prowl again. Buchwald wrote a column by that title for the New York Herald Tribune's European edition early in his career. He left school and moved to Paris in 1948.
When everyone is reading the newspaper and Mrs. Stevens says, "Everyone in Philadelphia reads the Bulletin", it's a reference to a long-running ad campaign for that newspaper. The ads were cartoons that showed something extraordinary going on, in a light-hearted vein, but no one sees it because they are all holding the newspaper in front of them. There is always one person who is not reading the Bulletin and trying frantically to get the attention of all the other people. The caption was always the same, "Nearly everyone in Philadelphia reads the Bulletin."
Towards the end, when Francie and her mother pass a newsstand with a newspaper reporting the burglar's death, Francie's Mother remarks, "In Philadelphia, almost everyone reads the Bulletin." Grace Kelly was a native of Philadelphia.
A completely coincidental bit of humor can be found in the scene on the bus where Robie looks to his right and sees a cage full of birds on the seat beside him, then looks the other way and sees Sir Alfred Hitchcock sitting at his left. Eight years later came the release of Hitchcock's The Birds (1963).
Filming on the French Riviera plays a pivotal role in Wu Ming's novel "54". The action takes place in the springtime of 1954, and nearly all of the characters in the novel (including Cary Grant, an Italian-American mafioso nicknamed "Steve Cement", and two Parisian gangsters from Rififi (1955)) cross each other's paths in Cannes and Nice.
During his lunch with Hughson, the insurance adjuster, Robie refers to his having been in the "burglary business". By definition, a robber uses force or the threat of force to steal. Burglary is illegally entering a property to commit a crime, such as theft. The jewel thief in this story is actually a burglar, not a robber.
According to Paramount Pictures production files contained at the AMPAS Library, Alec Coppel worked on the script for about a week in mid November 1954, shortly before the final set of retakes was done.
Mrs Stevens says that her husband didn't know they were sitting on 20 million barrels of oil. In 1955, when this film was made, a barrel of oil was worth just under $2.00 giving the Stevens a fortune of $40,000,000. In present day terms, that would be almost $400,000,000.