Zachary Scott does what he does best, i.e., plays a worm, in "Danger Signal," a 1945 B movie also starring Faye Emerson, Mona Freeman, and Rosemary DeCamp. Scott plays a writer who kills women after he gets their money. On the lam from his last murder, he rents a room in the home owned by the Fenchurch family, Hilda (Emerson) and her mother (Mary Servoss). Scott throws himself at Emerson, and she's dazzled. Mid-romance, her younger sister Anne (Freeman) comes home from a medical treatment. When she mentions that she was Uncle Wade's favorite and he left her $25,000 (big bucks by 1945 standards), Scott loses interest in poor Hilda and makes a play for Anne. Anne looks like Rebecca of Sunnybrook Farm until she starts sneaking around with Scott - overnight, she ages 10 years and becomes downright nasty to her sister. Finally getting the message that her tenant is no good, Hilda calls in a psychiatrist (Rosemary DeCamp) to psyche him out and advise her.<br /><br />Psychological dramas were all the rage during and after World War II, and Scott does an excellent job as a smooth sociopath. This was his forte - as a weak-willed sheriff in "Flamingo Road," he exhibited no real presence. As for two-timing, we saw him do that in "Mildred Pierce," where he proved himself particularly good at it. Emerson is a bookish stenographer with her hair pushed off her face and her big glasses, but after hours, she's lovely, and gives a strong performance. DeCamp was always an underrated actress - here, she sports a soft German accent and is delightful.<br /><br />This is a highly entertaining film though a very routine story. The acting truly elevates it.