At Whitney High School, a celebration is under way to welcome back Dodie Rogers, a student who had been absent from the school for one year due to an illness. The whole school turns out for her party, including sweetheart Freddie Trimball. When one of the guests at the party turns on the radio, the sweet sounds of singer Frankie Troy singing his tunes make the girls at the party scream and swoon with delight. The bobby-soxers at the recording studio where Frankie is singing also go wild, but Frankie later tells his sponsor, Buster Backer, and his agent, Jack Adams, that he has had enough of his teenage fans and wants a rest. The following day, newspapers around the country report the disappearance of the singing idol, and a thousand-dollar reward is offered by Adams to anyone who locates him. When students Roy and Jimmy learn about the reward, they devise a plan to get the money by using their pal, Freddie, who resembles Frankie, as a double for the singer. As part of their plan, Roy and Jimmy ask Lee Watson, one of the smartest students at the school and Freddie's best friend, to write a letter to Adams, informing him that Frankie is hiding at the school. The hoax goes according to plan until Jean Troy, Frankie's wife, arrives at the high school with her and Frankie's infant child. When Jean throws her arms around Freddie, Dodie tearfully concludes that her sweetheart has been unfaithful. Meanwhile, Adams, desperate to get Frankie back on the air, decides to broadcast his show live from Whitney High School. Chaos ensues at the dormitory when Jean, who believes that her husband has rejected her, leaves her baby in Freddie's room in the hopes that it will force her husband to return home. As the baby is passed from one dormitory room to another, a series of misunderstandings and broken romances result. The confusion is eventually cleared up when Jean returns to claim her baby, and when Frankie returns from his stay at a rest home. A short time before the radio show is to be broadcast from Whitney, Adams accepts the terms of Frankie's return to the stage, and Frankie agrees to perform with Freddie. During the show, Adams gives Lee the one thousand dollar reward, but Lee decides that his pals do not deserve the money, and instead donates it to the school milk fund.