Immediately before shooting, a bottle of silver nitrate was accidentally spilled onto Carole Landis' lips by her dentist. As a result, her lips were blue for more than three weeks, posing an added challenge for the makeup crew.
The writers used the name "Cornell" for the obsessive cop played by Laird Cregar, a tribute to noir writer Cornell Woolrich.
When Ed Cornell visits Jill Lynn in her new apartment, he notices a framed print on the wall and says, "The Garden of Hope. Do you believe in hope, Miss Lynn?" The print, "Garden of Hope," was a work by R. Atkinson Fox that sold widely in the 1920s.
When Laird Cregar went on a ride-along with L.A. police during the shoot, he was caught up in a real shooting. Cregar also reported for work shortly after an emergency appendectomy, against his doctor's orders.
The first noir film produced by 20th Century Fox.