Returning to France after a long exile, pianist Mathias Vogler reunites with his mentor, Elena, to prepare a concert. In a park, an encounter with a child who looks just like him will lead him to Claude, the woman he once loved.
After a gruelling final tour, Aurélien decides to settle in Japan with his wife Nanako, who is pregnant with their first child. As the young couple move into a traditional house in the Japanese countryside, Aurélien discovers an ancient suit of armour in a well, which is about to awaken strange creatures known as Yokaïs.
