Paul Muni plays a gangster who is murdered towards the very beginning of the story and is sent to Hell. This gangster seems an awful lot like his character from the movie SCARFACE (1932) and although Muni's acting is far from subtle, it is very entertaining. The Devil is also entertained by how awful the man is--especially since this evil deceased gangster looks just like a nice judge who he wants to discredit. Lucifer lets Muni out of Hell and gives him the judges body--and Muni being such a dumb mug never realizes that it's the Devil helping him or that he was even in Hell!! This seems like a big stretch, but considering the movie IS a fantasy, it can be forgiven. This plan all backfires, though, when Muni unintentionally does good as the judge and the Devil is less than amused.
The acting by Muni, as I said before, is pretty broad. However, Claude Rains is wonderful as a much more subtle Devil--one of the better ones Hollywood created--probably second to Laird Crager's version in HEAVEN CAN WAIT. All in all, this movie is just a lot of fun and has quite a few laughs as well. While not great theology, it's immensely entertaining.