Young-Sook and Mi-Ja meet as young girls in 1939 in Hado, a village on the island of Jeju, where traditionally the women earn a living while their husbands care for the children and home. The two girls begin training as haenyeo, divers who harvest oysters, sea slugs, and octopi from the sea. But after WWII when American occupation of southern Korea begins, the two grow apart. While Young-Sook struggles to make ends meet for her family, Mi-Ja’s husband’s role in the government spares her the economic suffering endured by most of the country. But after Mi-Ja’s family betrays Young-Sook, Young-Sook struggles for decades to reconcile her anger with fond memories of her friend, even after their families cross paths again.