French silkworm trader Hervé (Michael Pitt) is married to the beautiful Hélène (Keira Knightley). When an outbreak of disease ravages European silkworms, Hervé must travel to Japan to retrieve healthy eggs. After a long journey, Hervé finally arrives at a village where he can buy them. Here he becomes infatuated with a young concubine (Sei Ashina) and goes to great lengths to see her again. But, when war breaks out in Japan, the concubine flees, forcing Hervé to return home to his wife.