In the spring of 1945 in wartime San Francisco, Dudley Briggs, a U.S. Navy lieutenant, is promised a two-week furlough and a promotion by his ship's captain if he can secure a bottle of French champagne by the next morning to christen the U.S.S. Vengeance, the Navy's newest aircraft carrier. He races to a liquor store and discovers the city’s last magnum of French champagne, a rare luxury during the war, only to have it snatched away by the enchanting Margie Dawson, who is about to marry Torchy McNeil, an Army lieutenant and former Oregon football star he hasn’t seen in two years. Margie intends to place the precious bottle at her wedding reception, a gesture she hopes will seal a memory of joy rather than a lost romance.
Dudley follows the couple to their hotel, where a failed attempt to steal the magnum becomes a stubborn clash of plans and emotions. Undeterred, he engineers a rendezvous between Torchy McNeil and his ex-girlfriend, Rita Sloan. When Margie discovers the two together, she calls off the wedding and goes out with Dudley, intent on making Torchy pay for the hurt he caused. Their chase spills onto the Richmond Ferry, where Torchy McNeil confronts them and softly, but firmly, reminds the relationship that a marriage should have only “one quarterback.” And after Dudley hands over the magnum, Margie ends the moment with another split—yet there is a strange spark that lingers between them.
On the ferry, Dudley confesses that he loves Margie, though she suspects his feelings are entangled with the champagne and the mission. The moment is cut short when their actions are seen by their superiors, and the mood shifts from romance to consequence. The ship’s commanding officer, Captain Hornby, steps in, arrests the couple, and arranges for Margie herself to christen the ship with the bottle, turning a personal quarrel into a patriotic demonstration.
As the wedding countdown continues, Margie’s father, Mr. Dawson, arrives and finds Torchy in Margie’s robe, triggering a brief bout with law and order as he is brought to the Provost Marshal on a charge of insanity. The tension between duty and desire intensifies, but Captain Hornby intervenes to release Torchy, hoping to persuade him to relinquish the champagne. When the elder Dawson observes the situation, he believes Dudley truly loves Margie, and he urges Margie to return the bottle to the couple so they can see what happens next.
The finale pivots on a shared sense of patriotic responsibility. Torchy and Rita, initially reluctant to part with the trophy, are moved by the looming christening of the U.S.S. Vengeance and the broader war effort. Their transformation is sparked by a final, poignant act: Torchy delivers a flawless pass with the champagne, and Margie christens the ship, uniting love with national duty. In a tender coda, Margie receives a telegram from Dudley, inviting her to meet with the promise of a larger celebration—the biggest bottle of champagne she can find—for their wedding, sealing a future where romance and duty can coexist in wartime America.
