Adapted from the 1952 movie of the same name. Set in Hollywood in the waning days of silent screen era, it focuses on romantic lead Don Lockwood, his sidekick Cosmo Brown, aspiring actress Kathy Selden, and Lockwood's leading lady Lina Lamont, whose less-than-dulcet vocal tones make her an unlikely candidate for stardom in talking pictures. Don Lockwood is a silent film star with humble roots as musician, dancer, and stunt man. Don barley tolerates his vapid leading lady, Lina Lamont, who is convinced that their screen romance is real. After the first talking picture, The Jazz Singer, Proves to be a smash hit, the head of the studio, R. F. Simpson, decides he has no choice but to convert the new Lockwood and Lamont film, The Dueling Cavalier, into a talkie. The production is beset with difficulties, by far the worst being Lina's comically grating voice.

After a disastrous test screening, Don's best friend, Cosmo Borwn, comes up with the idea to overdub Lina's voice and they convince Simpson to turn The Dueling Cavalier into The Dancing Cavalier, a musical comedy film. Meanwhile, Don falls in love with an aspiring actress, Kathy Selden, who is providing the voice for Lina.