Six months following the end of World War II, navy wife Peg Blain receives a telegram from her husband, Cmdr. Jack Blain, asking her and their daughter Debby to join him in Sasebo, Japan, where he has been stationed as part of the occupation force. Peg and Debby, who have not seen Jack for four years, are thrilled that they will finally be a family again. With only five days to prepare for their journey, Peg and Debby hurriedly pack, undergo a battery of preventative shots and try to master some rudimentary Japanese phrases. Upon arriving in Sasebo, Peg, who is the first American wife to come to Japan, is gawked at by the local citizenry. Exhausted and feverish, Peg collapses and is subsequently diagnosed by Dr. Carter as having pneumonia. The doctor sends Akashi, a genial geisha at a local teahouse, to help run the household while Peg recovers, and Debby and Akashi become fast friends. Soon after, Capt. Hubert Arwin, Jack's superior, returns to Sasebo, and upon learning of Peg's illness, grumbles that women have no place with the occupation forces and warns they will only bring trouble. Jack, a lawyer, has been assigned to help write a new code of laws for the occupation, and meets with Mayor Yoshida and his son-in-law Ohara, the district attorney, to discuss the issue. When Jack mentions that his wife would like to meet Mrs. Ohara, the Japanese are shocked because they believe that a wife serves her husband by staying home and raising sons, not by socializing. However, when Ohara mentions Peg's request to his wife Mitsuko, she is intrigued. Ohara agrees to let her visit the Blains because as yet, Mitsuko has no children. At the Blain house, meanwhile, the four maids and two cooks hired to serve the family wreak havoc because of their unfamiliarity with Western electrical appliances such as refrigerators and vacuum cleaners. Once Peg has recovered, Akashi leaves the Blain household to return to the teahouse. As she departs, she observes that the difference between an American and Japanese marriage is that in America, marriage is considered a partnership, while in Japan, the man is the head of the house. When Mitsuko visits Peg she echoes the same sentiment and complains that Japanese men confide in geishas rather than their wives. Later, during a telephone conversation with Mitsuko, Peg agrees to teach her "how to change her husband" and begins by suggesting that she make him carry her packages and walk with her, rather than in front of her. Their conversation is overhead by the eavesdropping telephone operators, who decide to experiment with Peg's tenets. Meanwhile, Debby, who has discovered that the boys refuse to play baseball with her because she is a girl, bribes her way into their favor with offers of bubblegum. While at the baths one day, Ohara complains to Jack that Peg is trying to instill American values in Mitsuko by inviting them as a couple to dinner. That evening, as they await the arrival of their dinner guests, Jack asks Peg to curb her zeal in proselytizing for the American way of marriage. When Ohara refuses to attend the dinner because his wife was invited, Arwin chastises Peg for interfering in personal relationships. Later, Arwin summons Jack to his office and informs him that the mayor and Ohara are upset because women are demanding the same rights as men and orders him to have Peg tell the women that their first duty is to their husbands. When Peg creates a scandal by bringing Mitsuko to the teahouse in which her husband is conducting a meeting, Ohara demands that his wife show contrition. Instead, Mitsuko takes refuge with the Blains and refuses to come home. Furious, Arwin meets with Jack and the mayor and rails that women are ruining men's lives. Their meeting is interrupted by the sudden arrival of Amelia, Arwin's domineering wife, who accuses her husband of "making a mess of things." Arwin then gives Jack an ultimatum: either send Peg and Debby home to California or he will be transferred out of the unit. Blaming herself for Jack's predicament, Peg decides to try to appease Amelia and invites her to visit. When Amelia nonchalantly states that she plans to move into the house after it is vacated by the Blains, Peg asks her to come to a tea party the following day and meet Mitsuko. At the party, Amelia advises Mitsuko to follow her husband's wishes, but when Arwin comes to pick her up, Amelia upbraids and humiliates him for interrupting them. After Amelia leaves, Mitsuko decides to return to her husband, and when she discovers that she is pregnant, her father and husband blame her aberrant behavior on her pregnancy. Sensing that Arwin's contempt for women stems from the way Amelia treats him, Peg invites the captain to have tea with Jack. Instead of serving tea, however, she serves sake, and after getting him drunk, suggests that women like "masterful men." Inspired by Peg's advice, Arwin stands up to his wife, and soon after, a flustered and newly subservient Amelia tells Peg that Arwin has declared that he is now master of the house. On Christmas day, Debby invites the village children to come and experience the joys of Christmas. Arwin, Akashi, the mayor, Ohara and Mitsuko also come to wish the family a happy holiday. After the mayor concedes that allowing women to win small victories assures larger victories for their husbands, Arwin rescinds Jack's transfer, presents him with a promotion and orders for him to stay and complete his job.