The accountant Shohei Sugiyama (Kôji Yakusho) is feeling bored with his routine life, limited to hard work and stay at home with his wife Masako Sugiyama (Hideko Hara) and his teenager's daughter. One night, while traveling home by train, he sees the beautiful face of Mai Kishikawa (Tamiyo Kusakari) in the balcony of a dance school, and a couple of days later, he decides to visit the school and secretly take ballroom dance lessons every Wednesdays night. However, he becomes ashamed to tell his family his secret. Meanwhile, Masako feels the changes in the behavior of her happier husband, and hires a private eye to investigate whether Shohei is having an affair.