The Soul of a Monster (1944)

Golden Age Horror and Science Fiction (291 items)
list by Atomic Cinema

As famous surgeon, George Winson, lies on his deathbed, his wife Ann calls on unknown powers to save him. A strange woman (Lilyan) appears from nowhere and takes control. George recovers, but he's mysteriously dominated by Lilyan, and leaves his wife. When the evil woman tempts him into letting his best friend (Roger) die Wilson realizes that Lilyan wants his soul in exchange for the chance to continue living.