An arrogant orphan caught stealing jewelry is sent to a nautical school, where he learns a better code of behavior.
In London Geoffrey Braemer (Freddie Bartholomew) complains about hotel servants. Geof steals an emerald necklace by pretending he is ill, but he is caught by an insurance detective. Geof says his parents are dead, and he describes the couple who helped him. Geof is sent to a nautical school, where Captain Briggs (Charles Coburn) makes him carry his own bag. Bosun Crusty Jelks (Herbert Mundin) assigns Terry O'Mulvaney (Mickey Rooney) to help the four new boys. Geof gives Terry money to get his letters unopened; but Terry reports it to Briggs, who asks Terry to help keep Geof out of reform school. Briggs tells Geof he is overlooking his bribe, and Geof calls Terry an informer.
Geof sees the mail carrier and pretends to faint, trying to get a letter from Mrs. Briggs (Emma Dunn); but there is none for him. Geof already knows seamanship, but he falls from the rigging to a net. Geof quarrels with Mrs. Briggs, and his liberty is restricted. By apologizing Geof gets it back and goes to town. Little Albert (Terry Kilburn) tells Terry that Geof ran away. Terry finds Geof, and they fight. Terry knocks out Geof and gets a ride back. Only Terry is seen being late, and Terry won't tell Briggs why; so he loses his chevrons and chance to serve on the Queen Mary. Boys put the chill on Geof. Albert explains and asks Geof to fix it for Terry with Briggs. John Cartwright (John Burton) offers a cup for the winner of the boat race. Jelks makes Geof coxswain, and Geof enjoys giving orders. Geof's crew wins the race, and Cartwright gives Geof the cup.
Geof tells Briggs that Terry was bringing him back from running away. Geof gets liberty, and Doris Clandon (Gale Sondergaard) tells him he will get his share of the necklace; but Geof says he is going on the Queen Mary. Doris tells Jim Hampstead (George Zucco) that Geof has changed. Jim sews the necklace into Geof's coat. Terry and Geof make the Queen Mary, and Briggs explains to Geof he does not need reform school. Mrs. Briggs finds the emerald necklace in Geof's coat, but Geof says he didn't know it was there. Geof chooses school loyalty and names Doris. A boy sees Doris and Jim boarding the ship, telling them Geof is going to reform school. They try to get off but are caught by Terry and are arrested. In the final scene Geof reports on board and works with Terry and the others.
Geof's attitude is so obnoxious that the audience is relieved when he learns to be less selfish in following the example of the good Terry.