Sorry, Wrong Number (1948)

A wealthy spoiled invalid (Barbara Stanwyck) overhears a murder plot over the telephone when the wires get crossed. All alone in her mansion, she attempts to contact the police as well as her husband (Burt Lancaster) who should have been home hours ago but no one takes her seriously. Based on a 1943 radio play by Lucille Fletcher, the radio play was a half hour long and had a tour de force performance by Agnes Moorehead as the invalid in what was essentially a one woman show (it's available for listening on youtube). Well, a movie can't be a half hour long so the screenplay (also written by Fletcher) has been has been expanded to a feature length 90 minutes. Unfortunately, what this does is pad out the screenplay with lots of backstory flashbacks which dilute the suspense that was carefully built up in the radio play. The director Anatole Litvak and Stanwyck do manage to whip up the necessary tension in her present day scenes but every time they cut away to a flashback, the suspense dissipates. With Wendell Corey, Ed Begley, William Conrad and Ann Richards.