After he and a pair of accomplices, Al and Red, pull a $50,000 diamond heist, Slippy McGee separates from them and plans to hide out for a while in Middleton, a small town. A motorcycle-riding priest, Father Shanley, gives him a lift, then expresses his gratitude after Slippy saves a young boy from being hit by a truck.
In town, nurse Mary Hunter is asked by Dr. Moore to treat the newcomer's injuries. Slippy's monogram being noticed in his hat, he makes up the name "Steve Martin" on the spot. Mary's attentions to the patient stirs jealousy in suitor Tom Eustis, the richest man in town. Mary's rejection of his proposal infuriates Eustis, who sets out to ruin her father in business.
Al and Red turn up in town and decide to rob the bank. Suspicion falls on Slippy, who confronts his former partners and ends up killing Red in self-defense. When he decides to turn himself in to the law, Mary and others from Middleton say they'll vouch for his character and expect his return.