To fight the first signs of dementia, the same illness that took the life of his beloved wife, 71-years old Kenji joins the Long and Healthy Life Club, where he befriends the eccentric Mr Hashimoto. His biggest fear is becoming a burden to others, while Hashimoto struggles to come to terms with his failing body. In their quest to stay healthy, they decide to take a swimming class where they meet Kaori, a once-professional athlete turned swimming teacher. Like Kenji, Kaori struggles with the fact that she’s past her peak, but through the swimming lessons, they both find a new perspective on life.