Henpecked salesman Harry Saunders hates his job and is dreading the arrival of his fiftieth birthday. He is resigned to a bleak future when a sudden and unpremeditated act of courage propels him into a succession of dangerous but ultimately life-changing situations.

After Harry foils a robbery, he loses his job and allows himself to be drawn into dubious activities that he finds difficult to extricate himself from. His marriage goes steadily downhill and he becomes a pariah in his own family.

When good things start happening to him, Harry decides to confess what he has done, with unexpected results.