A tough street kid tries to use gang violence to break into corrupt city politics.

In a predominantly Irish slum in New York, sixteen-year-old Chuck Brennan has become the leader of a gang, in emulation of his father, who, Chuck believes, has become an important leader in ward politics without working at a job. To help Norah, a neighbor whose mother is taken to a sanitarium for tuberculosis, Chuck arranges for her to sing at a nightclub, but because she is underage, women from the Children's Aid Society arrive to take her to an orphanage. Julie Stone has recently inherited the tenement in which Norah and Chuck's family live, and with the help of the neighborhood doctor, she is trying to fix it up. Julie pays to send Norah to a private girls' school. During a fight between Chuck's gang and a rival Italian gang, Spike, a young black shoeshine boy, is killed when he tries to save Chuck from getting hit by a truck. After Chuck's mother blames him for Spike's death, he goes to ward boss Olden's office looking for work, but sees that his father is only Olden's stooge. Chuck then goes to work for gambler Blackie Davis, who is trying to shake down establishments in Chuck's neighborhood, but during a break-in at a laundry warehouse, Chuck tries to prevent Blackie from shooting the neighborhood cop Rourke, and both he and Rourke are shot. In the hospital, Chuck realizes that Blackie used him for a stooge and fought unfairly without giving Rourke a chance. He tells Rourke that he feels bad for calling his father a stooge and gives Blackie's address. After he turns seventeen, Chuck says goodbye to his parents, Julie and Norah, whom he hesitatingly kisses, and ships out with the Navy.