Lured

Lured is a 1947 film noir directed by Douglas Sirk and starring George Sanders, Lucille Ball, Charles Coburn, and Boris Karloff. This is a remake of Robert Siodmaks 1939 French film Pieges titled Personal Column in the United States.

Scotland Yard Inspector Harley Temple Charles Coburn asks if Sandra would be willing to work undercover to help find her missing friend and the killer. He sees firsthand how observant she is and gives her a temporary police identification card and a gun. Sandra is asked to answer personal ads, watched over by an officer bodyguard, H.R. Barrett George Zucco.By coincidence, she meets the dashing manabouttown stage revue producer Robert Fleming George Sanders. In the meantime, Sandra answers an ad placed by Charles van Druten Boris Karloff, a former fashion designer who is now mentally imbalanced. Barrett has to come to her rescue. ........

Source: Wikipedia