The film is a lengthy work interweaving characters from different backgrounds and social strata in a narrative centered around the experiences of its heroine, Yumie Sone. Over two hours long, Seven Seas was released theatrically in two parts, with the first part entitled "Virginity Chapter" coming out in December 1931, while the second part, "Chastity Chapter," followed in March 1932. Near the beginning of the narrative, at a garden party given by the wealthy Yagibashi family in Tokyo, Yumie meets Takehiko, the Yagibashis' playboy son and the brother of Yumie's fiancé, Yuzuru. Yumie, a young middle-class woman, lives with her ailing father, a retired ministry official, an older sister, and a younger sister still a child (played by a very young Hideko Takamine). Takehiko, who has just returned from a trip to Europe, is attracted to Yumie and contrives to have her stay overnight at his family's mansion where he takes advantage of her.

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