Shirō Kuroki, the adopted son of the Yamada family, shares a deep and mutual love with his foster sister, Kinuko Yamada. His commitment to political and social causes, however, provokes the anger of his foster father, who casts him out of the household. Forced into exile, Shirō faces hardship and struggle. The film was based on a serialized novel written by the poet Byakuren (real name Akiko Yanagiwara) and echoes the real-life scandal known as the Byakuren incident.