Uncredited producer John Huston conceived this project as a star vehicle for his estranged wife, Evelyn Keyes, as a sort of parting gift. She had long complained about her lack of challenging roles while under contract at Columbia. They were divorced by the time production began. Although more famous for her role in Autant en emporte le vent (1939), Keyes felt this to be the best role and best performance of her career.
Evelyn Keyes was deeply affected by the death of her father-in-law, Walter Huston, that occurred while the film was in production.
Novelist James Ellroy ("L.A. Confidential," "The Black Dahlia") once called this his favorite film and described it as "a masterpiece of sexual creepiness, institutional corruption and suffocating, ugly passion."
The uncredited voice of radio announcer John Gilvray heard throughout the film actually is that of uncredited screenwriter Dalton Trumbo. Of those working on the film, only Producers Sam Spiegel and John Huston, and Director Joseph Losey knew that the screenwriter was the blacklisted Trumbo. Losey had Trumbo record his voice-over late at night without the knowledge of any other cast or crew. He was paid $35 (equivalent to $760 in 2025) for this voice role. Because Trumbo was blacklisted, the screenplay was credited to his front, Hugo Butler, who himself was soon to be blacklisted. Trumbo was jailed in 1947 for refusing to testify before HUAC and his credit on the film was officially restored by the WGA in 2000.
The producer credit is for S.P. Eagle, who is in actuality Sam Spiegel, who co-produced the film along with an uncredited John Huston, under their Horizon Pictures banner.