Ronnie Bowers, a singer and saxophone player with Benny Goodman's orchestra has been placed under contract by All Star Pictures. They book him into the Hollywood Hotel, which is also the residence of All Star luminary Mona Marshall. The afternoon before the premiere of her latest movie, Mona is interviewed by Louella Parsons, who breaks the news that Mona will not get the lead in a new film. Because her heart was set on starring in this film, Mona decides not to go to the premiere and disappears from her hotel. Publicist Bernie Walton holds a casting call to find a woman who looks enough like Mona to pass for her at the premiere and finds Virginia Stanton, whose only work in Hollywood has been as Mona's stunt double. Since Mona's usual escort, Alexander Dupre, will spot the substitution, they assign Ronnie to be her date. Ronnie is smitten with Virginia while thinking she is Mona. The next day, Mona returns and, in a fit of temper, demands that Ronnie and Virginia be fired. Ronnie is dumbfounded by Mona's behavior until Bernie reveals that he is really in love with Virginia. Virginia gets Ronnie a job as a car hop, where director Walter Kelton overhears his singing. Kelton offers Ronnie a job dubbing Dupre's voice in the new Mona Marshall movie. Louella is so charmed by what she thinks is Dupre's voice that she invites him to sing with Mona on the Hollywood Hotel program. The studio asks Ronnie to dub the voice again, but Virginia negotiates a terrific deal for him. Then pretending to be Mona, she kidnaps Dupre, and Ronnie stands in for him at the studio. He is a big hit, and for an encore, Virginia once again pretends to be Mona and sings along with him.