'Miklós Rózsa (I)' hated working with David O. Selznick.

'Miklós Rózsa (I)''s score in this film inspired the career of film composer Jerry Goldsmith.

James Flavin is in studio records/casting call lists for this movie, but he did not appear or was not identifiable.

David O. Selznick wanted 'Miklós Rózsa (I)' to swell the orchestra from 14 violins to 28 as he had liked the effect that that had brought when Franz Waxman did it while scoring Rebecca.

David O. Selznick wanted much of the film to be based on his experiences in psychotherapy. He even brought his psychotherapist in on the set to be a technical advisor. Once when she disputed a point of fact with Alfred Hitchcock on how therapy works, Hitchcock said, "My dear, it's only a movie."

Alfred Hitchcock himself referred to the film as "just another manhunt wrapped up in pseudo-psychoanalysis".

Alfred Hitchcock persuaded David O. Selznick to buy the rights to the novel for $40,000.

Alfred Hitchcock was a big admirer of Salvador Dalí's work and realized that no one understood dream imagery better. David O. Selznick was opposed to using Dalí from an expense point of view, until he realized the marketing mileage that could be gained from such a hiring.

Alfred Hitchcock: about 40 minutes in, coming out of the elevator at the Empire Hotel carrying a violin case and smoking a cigarette.

After Alfred Hitchcock had suggested "Hidden Impulse" as a title, studio secretary Ruth Rickman came up with the title "Spellbound", which tested well in a pre-release survey.

Although the film is in black and white, two frames where the gun shot goes off while pointed at the camera are tinted red.

Early versions of the script used the words "sex menace", "frustrations", "libido" and "tomcat" in scenes involving the character of Mary Carmichael. These were eliminated when PCA director Joseph Breen strongly objected.

One of the first Hollywood films to deal with psychoanalysis.

Originally released with an overture before the opening credits, and exit music after the end title.

The dream sequence was designed by Salvador Dalí, and was originally supposed to run slightly longer. It included a scene in a ballroom with hanging pianos and still figures pretending to dance, folled with J.B. dancing with Dr. Peterson who turns into a statue. It was cut from the final film due to lack of time to appropriately build the set to scale (little people were used in the background to give the illusion of perception, which did not satisfy Alfred Hitchcock or Dali). Only part of it was filmed, and even less of it ended up in the release version.

The dream sequence was produced by "Poverty Row" studio Monogram Studios. Its initial efforts kept getting rejected by David O. Selznick until he hired leading production designer William Cameron Menzies to oversee the production. Alfred Hitchcock himself was barely involved.

The first preview took place on 27 September 1944, after which David O. Selznick deleted an opening montage showing treatment of mental cases. After principal photography was completed, Selznick was involved with sound re-recording of the dialogue and the editing, eliminating about 14 minutes of the film.

The gun blast in the end is hand painted. Alfred Hitchcock used a form of hand-coloring for the orange-red gun-blast at the audience.

The shot where the audience sees the killer's view down a gun barrel pointing at Peterson was filmed using a giant hand holding a giant gun to get the perspective correct.

The snow falling on John Ballentine and Dr. Peterson during the skiing scene was actually cornflakes.