This turned out to be a decent '30s gangster movie, not a lot different from a few others I've seen where Humphrey Bogart plays the bad guy and is the main adversary of the hero. Several films had James Cagney up against him; here it was Edward G Robinson.
Robinson plays policeman "Det. Johnny Blake," who goes underground, so to speak, by posing as a gang member to get the goods on them. (It's based on a real-life character.) Robinson, as usual, is very interesting to watch and is a tough guy BUT with a soft heart. In fact, he even feels bad about betraying the head crook because he has such principles of being a "straight shooter" that he doesn't feel right lying to anybody, even the gang leader "Al Krueger" (Barton MacLane).
Bogart plays "Nick Fenner," Al's number-one guy and is more of the villain than his boss. Joan Blondell gets second billing but that's not right because she's at least fourth in the amount of screen time and lines. There really is no real love interest in this movie; it's strictly a crime story.
When I first saw this movie, a little over a decade ago on VHS, I wasn't that impressed but last week, watching this on DVD, not only was the story better than I remembered but the picture was excellent. The blacks, whites and grays in here are beautiful. This was part of the "Tough Guys" DVD package and they did a wonderful job on the transfer.