Kitty Kelly, her brother Barney, and Mrs. Kelly are neighbors of Rosie Feinbaum and her mother, who live over the delicatessen of Moses Ginsburg on New York's East Side. Rosie is in love with young Morris Rosen, a hospital intern; Kitty loves Officer Pat Sullivan. With a gang, Barney attempts to hold up Ginsburg, and Officer Pat, pursuing the gang, wounds Barney in the shoulder. Although Kitty pleads with him, Pat places duty above love and takes Barney to a waiting ambulance. En route to the hospital, Kitty is comforted by Morris; Pat and Rosie, believing the other two to be on intimate terms, team up together. Mrs. Kelly is infuriated, and a dispute with the Feinbaums develops into a neighborhood battle. Pat withdraws from the alderman race to assure Barney's parole, the boy sets out to get revenge, and Ginsburg's shop is set afire during a battle; Morris saves Rosie, and Pat saves Kitty. The original lovers are united, along with Ginsburg and Mrs. Feinbaum.