In Atlantic City in the 1920s, music teacher Ray Henderson comes to visit his sister-in-law, actress Kitty Kane, who is rehearsing for a new musical revue. When Ray sits down at the piano to play a tune, songwriters Buddy "B. G." DeSylva and Lew Brown mistake him for the piano player sent by the union and ask him to accompany them. Although the show's director throws out the song, Lew and Buddy are pleased by Ray's performance and hire him as their accompanist. Together, Lew, the crude man of the streets; Buddy, the ambitious social climber; and Ray, the level-headed family man, work on a new tune to debut in the revue. After the show bombs, the three, broke but still determined to become successful songwriters, return to New York, where Ray sells one of Lew's songs that he has reworked. Buoyed by his success, Ray decides to give up teaching and move his family to New York, and Lew and Buddy make him their partner. Over the next few years, the trio has a string of hits, all starring Kitty, who has fallen in love with Buddy. Anxious to produce his own show, Buddy accepts the financial backing of a gangster named Manny, who insists that his no-talent girl friend, Perky Nichols, star. When Buddy discovers that Perky can neither sing, dance nor act, he fires her, provoking Manny to beat him up. Risking his own life, the pugnacious Lew slugs Manny and warns him to leave Buddy alone. On opening night, the boys worry that Manny will sabotage the theater, but the show goes on without a hitch. Later, at the after-show party, Buddy kisses Kitty, but their moment of intimacy is broken by a phone call from Al Jolson, who demands that the boys immediately write him a song for his new picture. To appease Jolson, they decide to quickly pen a lousy song, and lock themselves in a room. Shut out and ignored, Kitty leaves in a huff. Soon after, the morning newspaper is delivered with a rave review for their new show and a bulletin detailing Manny's murder. At Ray and his wife Maggie's anniversary dinner, Buddy, fresh from a socialite's yacht, pays an unexpected visit. The warm family celebration causes Buddy to consider settling down, but Ray advises him that marriage is not in his nature. Soon after, Buddy unilaterally announces that the three of them are launching a publishing firm and going into motion pictures. Although Lew resents Buddy not consulting them about business decisions, the three are soon on their way to Hollywood. When Buddy invites Kitty to attend the premiere of their new movie, she reluctantly agrees. Buddy, preoccupied with Twentieth Century-Fox studio head Winfield Sheehan, stands Kitty up and at the party afterward, Sheehan monopolizes Buddy. When Ray and Lew inadvertently discover that Buddy plans to continue producing pictures, they angrily barge into his meeting with Sheehan. After Sheehan's pushy assistant tries to strong-arm Lew, Lew slugs him and Buddy shoves Lew out of the room. After Lew and Ray storm out of the party, Kitty chastises Buddy for his callous treatment of Lew and then says goodbye to him for good. Their partnership dissolved, Ray and Lew decide to write a new show by themselves. After the tryout in Atlantic City flops, Buddy phones Kitty from Los Angeles to inquire about their welfare. After sobbing into the phone and hanging up, Kitty decides to go outside and get some fresh air. In the hotel hallway, she encounters Buddy, who explains he was just pretending to call from California to see if a reconciliation would be possible. Entering the hotel room, Buddy announces that he has quit his job as producer and then proposes changes to improve the revue. After the show becomes a hit, the three renew their partnership.