Capt. Jeremy Bradford has a particularly exciting luxury liner cruise in store when he's charged with transporting a troupe of opera singers to Rio de Janeiro. Anxious to become a singer herself, Bradford's young daughter, Polly, decides to skip out on school and sneak onto the ship before it departs. Angry that his daughter disobeyed him, Bradford puts her to work on the ship for punishment, but Polly has her own ideas about how to spend the trip.