Silk.

French silkworm trader Hervé is married to the beautiful Hélène. 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. He becomes infatuated with a young concubine 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.