The movie was adapted from a novel; The Bloody Spur by Charles Einstein (1953) which was based on a real murder case that took place in 1946. In that year, William Heirens killed three women and left a message scrawled in lipstick on a bathroom mirror after the second murder. In the message, he urged the police to catch him before he killed again. Because of this, the press dubbed him "The Lipstick Killer".
According to film noir historian Eddie Muller in the commentary for this film, Dana Andrews was drunk during the entire production. (Andrews himself admitted that he was an alcoholic in the 1950s.) Ironically, his character is drunk throughout half the film.
The sequence depicting the New York subway was filmed in the Pacific Electric Belmont trolley tunnel under downtown Los Angeles. Inter-urban streetcars doubled for the larger New York subway trains.
While Sandra White is only in the opening shot (the beautiful single woman attacked by the killer), her image adorns the poster artwork and subsequent VHS, DVD, and Blu Ray covers: screaming while facing a dark hand outlined in sizzling red.
Vincent Price's character mentions the Sands Hotel in Las Vegas. At the time of this film, it had only been in operation for four years. The doors first opened in 1952, and the hotel soon became synonymous with the famed Rat Pack. The storied property finally closed in 1996, and the new Venetian/Palazzo complex now occupies the space.