According to Orson Welles, this film grew out of an act of pure desperation. Welles, whose Mercury Theatre company produced a musical version of "Around the World in 80 Days," was in desperate need of money just before the Boston preview. Mere hours before the show was due to open, the costumes had been impounded and unless Welles could come up with $55,000 to pay outstanding debts, the performance would have to be canceled. Stumbling upon a copy of "If I Die Before I Wake," the novel upon which this film is based, Welles phoned Harry Cohn, instructing him to buy the rights to the novel and offering to write, direct and star in the film so long as Cohn would send $55,000 to Boston within two hours. The money arrived, and the production went on as planned.

"Columbia Pictures" boss Harry Cohn told Orson Welles he would never again hire one man to produce, direct and act because he could never fire him.

Near the end of shooting, Orson Welles told "Columbia" executives that he wanted a complete set repainted on a Saturday for shooting on Monday. Columbia exec Jack Fier told Welles it was impossible, because of union rules and the expense that would be incurred by calling in a crew of painters to work on a weekend. Welles and several friends broke into the paint department that Saturday and repainted the set themselves, and when they were finished they hung a banner on the set that read "The Only Thing We Have to Fear is Fier Himself." When the union painters arrived at work on Monday and saw that the set had been repainted by someone else, they refused to work, threw a picket line around the studio and threatened to stay on strike until a union crew was paid triple time for the work that had been done (which was why Fier had refused to authorize the work in the first place). To placate the union, Fier agreed to pay them what they wanted but put the cost on Welles' personal bill. In addition, he had the union painters paint a banner saying "All's Well That Ends Welles."

In the aquarium scene, the tanks were shot separately, enlarged, and matted in to make the sea creatures appear more monstrous and looming closer to the actors.

Orson Welles runs past an old Mexican movie poster of "Resurrection (1927)" during a chase scene. The film stars Dolores del Rio, a former girlfriend of Welles'.

The yacht on which much of the action takes place was the "Zaca," which was rented from its owner, Errol Flynn. Flynn skippered the Zaca between takes, and he can be spotted in the background in a scene outside a cantina.

Columbia Pictures chief Harry Cohn thought the movie would ruin his star, Rita Hayworth, and held the release back for one year. Cohn ordered director Orson Welles to insert "glamour" shots (close-ups) of Hayworth. Because of the success of Hayworth's singing in other films, Cohn ordered filming of the scene where Hayworth sings "Please Don't Kiss Me."

An assistant cameraman, working bareheaded in the blazing sun, suddenly dropped dead of a heart attack. The often-drunk Errol Flynn tried to put him into a duffel bag, and Orson Welles immediately sent someone ashore to alert authorities before Flynn could bury the man at sea.

Orson Welles' decision to have Rita Hayworth cut her hair and bleach it caused a storm of controversy, and many in Hollywood believed it contributed to the film's poor box-office returns.

Everett Sloane refused to wear the leg braces constructed for his character, complaining bitterly of the pain they caused. Sloane was reportedly impossible to deal with and shunned everyone on the set.

Orson Welles was very displeased with the score put together by the studio-appointed composer. In a test screening, he put a temp stock score on which was supposed to be a model for the composer. The composer completely disregarded Welles' precisely laid-out blueprint. In particular, the final mirror scene was supposed to be unscored, to create the sense of terror.

Orson Welles' original rough cut of this picture ran 155 minutes. Numerous cuts made by Columbia Pictures executives included a shortening of the famous "funhouse" finale.

During reshoots, Orson Welles was forced to match shots of Rita Hayworth with a stand-in, who was paid $500 to have her hair cut and bleached like the star.

The Mexico shoot was plagued by a number of problems, many of them detailed by producer William Castle in his diary. During the day the temperature was usually blisteringly hot, and at least once Rita Hayworth collapsed from the heat. At night millions of poisonous insects swarmed around the arc lights, often blotting them out. One insect caused a substantial delay in shooting when it bit Orson Welles and his eye swelled shut to almost three times its normal size.

Orson Welles never viewed the rushes. He just shipped them off to Viola Lawrence, Columbia's chief editor, who had been assigned to the picture. When she saw that Welles had not shot a single close-up, not even one of Rita Hayworth, she went immediately to Columbia boss Harry Cohn, who ordered the director to film some. On location Welles ignored the command, although he finally complied upon his return to the studio.

Orson Welles originally wanted the sound be a disruptive element in the film, a device to unsettle the viewer (such as keying voices in at such a low level a viewer would have to strain to make out what was being said). Except for a few minor instances of this effect (the grating voices of Bannister and Grisby, the overdubbing of the final dialogue in the Hall of Mirrors), almost all were "corrected" by the Columbia sound department.

Orson Welles thought of Everett Sloane as primarily a radio actor who didn't move particularly well on film, so he introduced crutches to the character.

Some scenes were filmed close to a crocodile-infested river. The rock from which Elsa dives into the ocean had to be scraped to remove poisonous barnacles. A Mexican swimming champion armed with a spear had to swim off camera near Rita Hayworth to ward off deadly barracuda in the waters.

For one shot simulating O'Hara's point of view as he hurtled down the slide, Charles Lawton Jr. and camera operator Irving Klein slid the entire length of it on their stomachs with the camera on a mat.

When the film was screened for "Columbia Pictures" president Harry Cohn, he found it so incomprehensible he offered to pay $1,000 to anyone who could explain the plot to him. Later he decided to clarify the film by beginning it with the trial scene and telling the preceding part of the story in flashbacks, but abandoned the plan because so much new footage would have had to be shot it would have nearly doubled the film's cost.

Orson Welles wanted to pattern the funhouse on the expressionist images of "The Cabinet of Dr. Caligari (1920)." Stephen Goosson designed an elaborate set with sliding doors, distorting mirrors and a 125-foot zigzag slide from the roof of a studio sound stage down into a pit that was 80 feet long, 40 feet wide and 20 feet deep.

Errol Flynn's own pet dachshund is seen in the yacht scenes, since it is Flynn's yacht "Zaca" in the film. Flynn also did all the aerial photography for that film's yacht scenes and is in the film incognito.

The cast was frequently frustrated and confused by arriving on the set to find Orson Welles rewriting the script from day to day. His method of working with his actors was often harsh and manipulative. Sometimes he deliberately rattled them to get nervous, edgy performances. Other times he would cause them to forget their lines so they could improvise new ones. One such line that survives on screen was made up on the spot by a flustered Erskine Sanford as the judge: "This isn't a football game!"

After distinguished service during WWII in coastal patrol off California, the "Zaca" was sold out of Errol Flynn's estate and went through years of neglect and disputes in ownership. Rescued from certain destruction and restored by a wealthy Italian businessman, it sails now out of Monte Carlo, and is recognized as one of the finest yachts in the world.

Shooting was delayed whenever Errol Flynn disappeared for extended lengths of time. His contract stipulated the yacht could not be used unless he was present.

When Glenn Anders arrived on the set his first day, Orson Welles immediately ordered him to lie down on a stretcher under a sheet and play dead. The actor did as instructed and while he lay there, he said a studio rep handed him a pen and a contract to sign. At that point, Anders claimed, he still knew nothing about the film or the part he was playing. Over the course of shooting, Anders became so upset about Welles' bullying, the crew dubbed him "Glenn Anguish."

Errol Flynn was paid $1500 per day for the use of his yacht, plus lunches for his crew.

Rita Hayworth became ill while shooting in Mexico, and the production had to close down for a month. Orson Welles had been unfairly criticized for having the film go over budget.

The Hall of Mirrors maze was designed with the help of special effects wizard Lawrence W. Butler, who had provided the screen magic in such films as Things to Come (1936) and The Thief of Bagdad (1940). It contained 2,912 square feet of glass. Some of the mirrors were two-way, allowing Charles Lawton Jr. and his crew to shoot through them. Other times they shot through holes drilled in the glass.

Other titles considered for the film were "Black Irish" and "If I Die Before I Wake," the title of the novel upon which the film was based.

As the temperature rose and the shoot stretched longer than planned, financial problems worsened, and the studio began sending memos and emissaries to find out what was going on. One of the biggest sources of delay was Orson Welles himself, as William Castle noted frequently in his diary: "His whims and demands many, he has spent the first week picking locations, then changing his mind and picking others."

Shooting aboard the close quarters of the yacht presented special challenges, which Orson Welles and Charles Lawton Jr. turned to good effect through the use of cramped, claustrophobic compositions. But shooting against the glare of the sea and sky often rendered light meters useless, causing over-exposure. A series of experimental tests were made to figure out how to overcome the problem.

In a scene in Acapulco, the song "Amado Mio" is playing in the background. Rita Hayworth famously performed this song in "Gilda (1946)," released two years earlier.

The Central Park scene was shot using a carriage that was bought in Mexico and shipped to New York. Huge arc lights, a sound boom and a 20-foot camera crane followed the carriage nearly a mile to get a single dolly shot. Unfortunately, it was later cut by the editor Columbia brought in to "fix" the picture, completely ruining Orson Welles's concept.

In the scene where Mrs. Bannister goes to the Chinese theater in search of Michael, she speaks Cantonese, a Chinese dialect spoken mostly in southern China and Hong Kong.

Of the music accompanying Elsa's dive into the water, Orson Welles said it was more suitable "for some antic moment in a Silly Symphony, a pratfall by Pluto the Pup, or a wild jump into space by Donald Duck."

The Funhouse/Hall of Mirrors sequence took extensive work. The two sets were actually intended to be separate locations (as they were in San Francisco's Playland where the exteriors were shot). A scene in an earlier draft of the script would have made that clear and explained not only how the characters got from one to the other but how they were able to enter the closed attractions.

Wide-angle lenses were used to lend distortion to close-ups.

The character played by Everett Sloane describes himself at one point as the son of "a Manchester Greek," an in-joke reference to Orson Welles' frequent stage and radio collaborator George Coulouris (most famous for playing Mr. Thatcher in Citizen Kane (1941)), who was the son of a Greek immigrant to the UK and who was born in the city of Manchester.

Filmed in 1946, not released until 1947.

More than 35 days were spent on location in and around Acapulco.

A remake of this movie came close to production from producers John Woo and Terence Chang, and screenwriter Jeff Vintar. The script was based on both the original Orson Welles screenplay and the original pulp novel by Sherwood King, entitled "If I Die Before I Wake." Brendan Fraser was eyeing the Welles role of Michael O'Hara and wanted Michael Douglas and Catherine Zeta-Jones to play Arthur and Elsa Bannister. The project was suddenly scuttled when Sony Pictures studio head Amy Pascal decided to focus primarily on "teen pictures."

Acclaimed Director of Photography Rudolph Maté's uncredited work on this film would mark his last work in that position; he would finish out his career in the director's chair.

Orson Welles and cinematographer Charles Lawton Jr. had lengthy pre-production conferences during which they decided to use low-key interior lighting and natural light wherever possible. Filters were used for the outdoor skies to keep the transitions between outdoor and indoor scenes from being too glaring. Stark contrasts were set up in exterior shots to achieve some dramatic facial modeling. For instance, in a scene between O'Hara and Grisby, Welles wore a white linen suit to make his face look dark and somber.

Film debut of Ted de Corsia.

Orson Welles originally wanted Barbara Laage for the lead.

Orson Welles spent more than a week from 10:30 at night until 5:00 a.m. painting the set.

Was selected for preservation in the National Film Registry in 2018, by the Library of Congress for being "culturally, historically or aesthetically significant."

Glenn Anders was paid a salary of $1250 per week for the protracted shooting of the film.

Included among the "1001 Movies You Must See Before You Die", edited by Steven Schneider.

Included among the American Film Institute's 2001 list of 400 movies nominated for the top 100 Most Heart-Pounding American Movies.

Glenn Anders, who played George Grisby, said he shot the scene in which his character's corpse is carried away on a stretcher before he filmed any of his part as a live person. He signed his final contract for the film while lying on the stretcher.