When United States Marine Woody Davis starts a fight while on liberty, he and his cronies, Tubby Waters and "Mac" MacDonald, are arrested, and Mac, who is due for a promotion, is warned against becoming too devoted to his trouble-making friend. In Shanghai, Woody and Tubby go to the Bar Russe looking for "Russian blondes," and hear a stranger, Drenov, insult America. Woody starts a brawl in which Tubby is killed by Drenov and Woody is then dishonorably discharged from the Marines. With the help of "Brooklyn," a fast-talking demimonde from New York who witnessed Tubby's murder, Woody discovers that Drenov works for the Transpacific Mining Supply Co., which acts as a front for gunrunning for Chinese rebels. Woody goes to the gunrunners' office and struggles with Drenov, who has a gun, and the Russian is killed. Drenov's boss, Corrigan, then offers Drenov's job to Woody, who says he has no loyalties to either side in the war. While smuggling ammunition in a staged funeral procession, Woody sees his old friend Mac, who is now a lieutenant assigned to fight contraband in Shanghai. After Drenov's body is pulled from the river, Enrico "Rico" Venetzi, the bartender of Bar Russe, is interrogated regarding Tubby's murder, and Brooklyn leaves to warn Woody, who is waiting with Corrigan for a shipment at the international settlement outside Shanghai. There, an American businessman calls for Marine protection when he learns that Chang, leader of the rebels, has crossed the border. Woody then tells Corrigan he is out of the deal if the Marines arrive. The Marines do arrive and Mac learns that Woody is involved with Corrigan, the gunrunner they have been looking for. Mac and Tex, his partner, then arrest Woody just as Chang and his rebels arrive. Chang, believing Corrigan to be a traitor, shoots him, and ties up Mac and Tex. While the Marines fight the rebels, Woody shoots Chang and releases Mac and Tex, handing over the contraband to the Marines. As the rebels enter the warehouse, Woody blows it up with a grenade. Although the Marines win the battle, Tex dies, and Woody and Mac are wounded. While recovering in a hospital, Woody is reinstated in the Marines and sent to the Philippines, where Brooklyn is to meet him.
