Yahoo Web Search

After straight-arrow district attorney Joseph Foster (Thomas Mitchell) says in frustration that he would sell his soul to bring down a local mob boss, a smooth-talking stranger named Nick Beal (Ray Milland) shows up with enough evidence to seal a conviction. When that success leads Foster to run for governor, Beal's unearthly hold on him turns the previously honest man corrupt, much to the displeasure of his wife (Geraldine Wall) and his steadfast minister (George Macready). Wikipedia