Joan Manning, the daughter of a police sergeant, secretly marries Chick Williams, a gangleader who convinces her that he is leading an honest life. Chick attends the theater with Joan and, at the intermission, sneaks away, committing a robbery during which a policeman is killed. Chick is suspected of the crime but is able to use Joan to substantiate his alibi. The police plant Danny McGann, an undercover agent, in Chick's gang; but he is discovered, and Chick murders him. Chick is later cornered by the police in his own home. Before they can arrest him, he flips the light switch, plunging the room into darkness. In the midst of the chaos, Chick escapes to the roof. He attempts to jump off to a nearby building, but stumbles on the landing, thus falling to his death.