Michael Mann at the peak of his abilities as a filmmaker with this film. Thief is an excellent crime/noir film. James Caan is a top professional thief trying to go straight and even adopt a more normal life as a married man with a family. Tuesday Weld is his girlfriend/wife. The actor Robert Prosky is the Chicago mob boss who thinks he has Caan under his thumb.
The film is stylishly filmed and has an interesting score by Tangerine Dream before they became kind of a film music cliche.
Mann wrote the screenplay the film runs 123 minutes.