Steve Costigan, a sailor in Hong Kong, is broke and desperate. He encounters Smoky Jones, who tries to borrow money from him. When Costigan refuses, a fight ensues, but they are separated when the lights go out. Costigan later discovers that his dog, Mike, has been stolen, and a note demands fifty dollars for his return. Costigan goes to the Quiet Hour Arena to raise the money by fighting, and ends up taking a bout on short notice. After winning, he leaves the money as instructed but finds out it's been stolen. He confronts Smoky Jones, who confesses to the theft and reveals that the dog is with a group of Chinese actors. Costigan tracks them down, only to learn that they had arranged a fight between Mike and a gorilla. He intervenes, fights off a mob, and is informed by a policeman that Mike and the Chinese actors, along with the gorilla, are treed at the edge of the city.