An affluent medical professor, Komiya, and his bossy wife, Tokio, are to look after their high-spirited niece, Setsuko, from Osaka. Setsuko is a liberated woman who does what she wants, including smoking, even though she is a minor. On Saturday, the professor does not feel like going to his weekend golf game, but his wife packs him off anyway. So he leaves his bag at the apartment of his student Okada, and goes to a bar with a friend.
Setsuko traces him there, and insists that he take her to a geisha house. When she gets rather tipsy, the professor calls Okada to take her home, while he sleeps at Okada's. The wife becomes suspicious of Setsuko when she sees Okada bringing her home, and also of her husband when she discovers that he did not go golfing.
The next day, Komiya is surprised by Setsuko's request to see him in the morning. He agrees, but warns her that he has a busy schedule. Setsuko asks him to take her to the beach for a picnic, and he agrees. As they walk along the beach, Setsuko tells Komiya about her life as a liberated woman, and how she feels free to do whatever she wants. Komiya is impressed by her confidence and openness, and they spend the afternoon together.
When they return to the hotel, Setsuko asks Komiya if he has ever been to Japan. He explains that he has never been, but he would love to visit one day. Setsuko suggests that they go together, and they agree to meet up later that evening.
As they are leaving the hotel, Setsuko asks Komiya if he has any plans for the weekend. He explains that he has a golf tournament the following day, and that he needs to get some rest. Setsuko suggests that they could go to the beach again on Sunday, and he agrees.
On Sunday, Komiya wakes up early and heads to the beach. Setsuko follows him there, and they spend the day enjoying each other's company. When it starts to rain, they head back to the hotel.
The next morning, Komiya is surprised to find Setsuko waiting for him at the hotel lobby. She explains that she has decided to stay with him for the weekend, and that she wants to explore more about Japan. Komiya is happy to have her here with him, and they plan to visit various places around Tokyo.
As they are walking around the city, Setsuko introduces Komiya to some of her friends and acquaintances. They all seem very friendly and welcoming, and Komiya is impressed by the warmth of their hospitality.
One day, they decide to go to a traditional tea house for tea and snacks. The atmosphere is peaceful and relaxing, and Setsuko seems to enjoy it immensely. Komiya is impressed by her appreciation for Japanese culture, and he realizes that he has been missing out on some of the best parts of his life by staying in his comfort zone.
As the weekend draws to a close, Komiya and Setsuko say goodbye to each other. They both express their gratitude for spending the time together, and promise to continue exploring Japan together in the future.
