After receiving his military discharge, singer Don Collins proceeds to the address of the pen pal who corresponded with him while he was overseas. Helen Tyler answers the door and is perplexed by Don's expression of gratitude until she realizes that her teenage sister Susie is the singer's mysterious correspondent. The Tylers invite Don to dinner, and at the table, he inadvertently offends Helen, a schoolteacher, when he criticizes all teachers. When Don speaks of the difficulty he has experienced finding a singing job, Susie decides to organize a fan club to launch Don's career. Enlisting the help of her neighbor and would-be boyfriend, Howard Barnes, Susie writes a stack of fan letters and asks her relatives from around the country to post them. When R. N. Swanson, the owner of the local radio station, receives a deluge of letters in praise of Don, he hires the singer to appear on a radio spot.