At the New York branch of Mammoth Studios, motion picture animator Linda Fay and her boss, Bob Adams, search for a singing voice for their star cartoon, "Paddy the Pig." Linda holds auditions in her apartment, but a neighbor, disturbed by the noise, calls the police. Officers Jimmy Duffy and Joe Nash answer the call and sell Linda tickets to the policeman's ball after cautioning her to keep the noise down. As Jimmy ushers one of the singers out, he instructs him on how to sing. Linda hears his beautiful voice and eagerly awaits the ball. Linda, Bob, their pianist Sidney and secretary, Mabel Dunne, attend the ball and agree after Jimmy sings that he has the voice they need. The others then convince Linda to hire Jimmy without telling him that he is supplying the voice of a pig, but instead, letting him think that he will be a real actor. Two weeks pass as Jimmy records Paddy's songs, and he and Linda rapidly fall in love. Bob is jealous because he also loves Linda, but he realizes that...