In New York City, Italian American songwriting brothers Phil and Freddie Russo turn out one successful song after another for their publisher, Sanders. One day, Freddie and Phil accept an invitation from attractive June Larkin to sing at a benefit that her parents are hosting. Kitty, the brothers' secretary, is secretly in love with Phil, but Phil is smitten with June. Following the benefit party, Kitty visits Phil and Freddie's mother, who lives alone in an East Side tenement, and asks her to help stop the bickering between her sons. Mrs. Russo tells Kitty that she has refused to play favorite with either son, and that she has turned down separate invitations from Phil and Freddie to live with them. Joe, a milkman and an aspiring songwriter who adores Mrs. Russo, drives Kitty home and, en route, recites the lyrics of one of his new songs. Later, Mrs. Russo throws a party to bring her sons together, and they sing a song written especially for her. Mrs. Russo eventually consents to live with her two sons in a large apartment, but the arrangement soon sours when the two brothers become embroiled in a jealous rivalry over June. The dispute results in Freddie moving into his own apartment. Although Freddie refuses to speak with Phil, the brothers manage to continue writing songs together. However, when the feud begins to take its toll on the quality of the brothers' songs, Sanders tells Freddie that he will no longer publish their work. Frustrated by his inability to find a new publisher, Freddie decides to start his own publishing business. The company makes little money, and goes bankrupt soon after, but Freddie refuses to accept financial help from band leader Jimmy Dorsey. Later, Kitty enlists Joe's help to force a reconciliation between the estranged brothers. As part of Kitty's plan, Joe poses first as a lyricist and then as a composer, tricking the brothers into collaborating on a musical comedy without the other's knowledge. The show appears destined for success until the brothers discover the ruse and threaten to stop the show with an injunction. When Mrs. Russo tells her sons that she has invested heavily in their show, however, they call off their injunctions and allow the show to go on. The show is a hit, and the two sons are finally reconciled.