Melodrama that takes place in Montmartre about a cat burglar nicknamed The Rat who promises to look after an innocent young girl. His involvement with a rich woman could be his downfall.
Jean Boucheron (Anton Walbrook) is a jewel thief known as The Rat. His friend Pierre is about to be executed and asks him to look after his young daughter Odile (Rene Ray). Odile is being looked after by a dressmaker who has some plans for her. Jean lives over a bar and Odile moves in with him. He puts the word out that everyone is to leave her alone.
A police inspector has been trying to catch Jean for years. He comes into the bar with Zelia de Chaumont (Ruth Chatterton) and her rich fiancee Luis Stets. Earlier that day Luis bought her an expensive string of pearls which she wears on her wrist. She starts flirting and then dancing with Jean. After Jean notices the pearls Luis notices Odile. Jean lets him know to keep away from her. Odile came downstairs to warn Jean that the cops were searching his place. The Inspector leaves when nothing is found.
It looks like a romance will bloom between Jean and Odile. Then he breaks into Zelia’s home intending to steal the pearls. They have some conversation and he leaves without them. The two start meeting each other in various places even though some of Jean’s friends say it’ll leave him with nothing.
One night at Zelia’s Luis argues with her and she gives him the pearls back and says she’ll return all other gifts. Jean comes over and after getting by the snooty butler starts romancing Zelia. Meanwhile back at Jean’s flat Luis is coming on strong to Odile.
Zelia tells Jean about giving the pearls back and they start to argue. The phone rings and it’s one of Jean’s friends telling him about Luis and Odile. He rushes out and grabs a cab to speed back. Luis starts to attack Odile and she shoots him dead. While climbing up to get into the window Jean falls and breaks his arm.
Odile is arrested for Luis’ murder. She’s not talking about the circumstances. Jean goes to the police station and says he killed Luis. The two are put on trial where Odile remains silent and Jean insists he did it.
It’s a predictable ending but overall it’s not a bad movie and one of those to watch if your movie supply is running low.