While on a tour of the naval yard, officer Biff Martin gets into an argument with civilian iron worker Chesty O'Conner. Their quarrel escalates that evening at the iron workers' ball when Biff dances with Chesty's girl, Gladys Hawkins. Chesty loses his job as a result of their fight and decides to join the Navy in order to get even with Biff. After his ninety days training in San Diego, Chesty and his friend, Wilbur "Droopy" Mullins, are assigned to Biff's ship, the U.S.S. Arizona . To Chesty's disappointment, Biff informs him that all private fights must be postponed until they are ashore. In the meantime, Chesty has to follow Biff's orders as he is the senior officer. Biff's sister Dorothy comes aboard ship to visit her brother. Not knowing she is Biff's sister, Chesty decides to win Dorothy for himself. After learning that she works at the telegraph office, Chesty and Droopy visit there that evening, intending to wire Droopy's mother money for a new pair of false teeth. Dorothy invites Chesty to her apartment for a home cooked meal, and misunderstanding her intentions, Chesty makes a pass at her. She rebuffs him, and Chesty, who genuinely likes her, changes his attitude. While he is at Dorothy's, Biff walks in and throws him out. Biff then demands that Dorothy stop seeing Chesty, but she refuses, asking him instead to try to make friends with Chesty. When Chesty asks for special leave to visit Dorothy, however, Biff prevents it. Angrily, Chesty sneaks ashore in disguise, determined to quit the Navy. After Dorothy tells him she could never love a quitter, he returns to the ship, where he is court-martialed for being away without leave. The other sailors ostracize Chesty because of his attitude toward the Navy. When Dorothy defends Biff's actions, Chesty breaks up with her. Despite his dislike of the Navy, Chesty risks his life to put out a fire in the gunroom and receives a medal, which he does not take seriously. Finally the Navy transfers him to the dirigible field ashore. The dirigible is sent to San Pedro for Navy Day. While helping to land the air craft, Biff gets tangled in the ropes and is towed aloft. Chesty asks permission to rescue him, and when it is denied, he climbs down the rope anyway, parachuting to safety with Biff. Chesty and Dorothy are reconciled, and Biff gives the bride away when they marry. Chesty has the last laugh when he is promoted over Biff.