Nanette (Doris Day) has dreams of Broadway, but lacks the funds to stage the musical her boyfriend, Larry (Billy De Wolfe), has written. After extracting a promise from him to make her the star of the show, Nanette turns to her wealthy uncle (S.Z. Sakall) for the money. He agrees to lend her the $25,000, but on one condition -- that for an entire day she must answer "No" to any and all questions. Though she readily agrees, Nanette soon realizes the bet is easier made than won.