The first segment of the film introduces the protagonists, a woman named Su Jin and a man named Chul Soo. The movie highlights their accidental meeting, followed by their subsequent courting despite the social standings that should have kept them apart. Kim Su-Jin is a 27-year-old fashion designer, spurned by her lover, a colleague who was also a married man. Depressed, she goes to a convenience store, where she bumps into a tall, handsome man with whom she has a slight misunderstanding. Following that, she returns home and, receiving her father's forgiveness, decides to start life afresh.
One day while accompanying her father, who is the head of a construction site, she coincidentally meets the man whom she earlier bumped into at the convenience store. He is Choi Chul-Soo, the construction site's foreman who is aiming to become an architect. Chul-Soo may appear like a rough and dirty construction worker initially, but exudes sheer masculinity in its most basic physical form. Su-Jin instantly takes a liking to Chul-Soo and in what is a refreshing change, actively courts him. There are many sweet events that take place in the occurrence of their courtship, eventually leading to their marriage.
The second segment follows the couple settling into married life. Su-Jin learns to be a housewife as her husband cares for her. As the segment progresses however, Su-jin begins to display forgetfulness, including an incident in which a fire breaks out because of a forgotten stove. While Chul Soo caught the fire in time, the seriousness of the incident and others like it draw them to seek medical help.
The third segment involves the revelation of Alzheimer's disease and the couple's consequent response to it. Su Jin is heavily burdened by the knowledge that she will forget her husband and hides it from him until he seeks advice from the doctor himself. Despite the disease, they make the commitment to stay together and as the disease progresses, the trials the couple go through increase because of Su Jin's consistent loss of memory.
The fourth segment reveals Su-jin in the final stages of the disease and the grief Chul Soo experiences because of it. Yet he remains beside her, despite her lost memory, hiding his eyes behind sunglasses when he visits her so she can't see his tears. The end of the movie finishes off with Chul Soo replaying the first time they met in the convenience store with all her friends and family there. In the final scene, Su-jin is riding beside her husband in the car in the sunset, and he can finally tell her, "I love you."
