Anju, the teenage daughter of an aristocratic family in feudal Japan, saw her life shattered when her father, gamekeeper to the Mikado, faced false accusations of arson from a jealous noble. This led to his exile and trial in Kyoto. Orders soon demanded her family surrender their estate to a new owner, compelling Anju, her younger brother Zushio, their mother Yashio, and a loyal maid to flee.

Bandits deceived and scattered the family during their escape. Anju and Zushio were captured and sold into brutal slavery under the cruel Lord Sansho, enduring harsh labor. Amidst their suffering, Anju focused on protecting Zushio and nurturing their hope of reuniting with their parents.

Recognizing the direness of their plight, Anju eventually urged Zushio to escape Sansho's compound alone, seeking aid from Fujiwara, a noble in Kyoto and their father's former colleague. She understood Sansho would likely torture her for information about Zushio's flight.

Following Zushio's escape, Sansho's kind-hearted son Saburo helped Anju flee the estate. Her fate then took a mystical turn. To evade capture and interrogation that could endanger Zushio, she transformed into a white swan, gaining power over the element of air. She flew to freedom, transcending her physical suffering.

As a swan, Anju's spirit visited Saburo, who had become a monk. She communicated silently with him as he gazed upon a wooden statue he had carved in her likeness, revealing her enduring connection to those who showed her kindness.

Later, after Zushio gained power, confronted Sansho, and freed the slaves, he journeyed with Saburo to find their mother. They paused to pay respects at the carving of Anju. In that moment, Anju appeared as a swan in the distance, confirming her ongoing spiritual presence and watchfulness over her family. Her transformation represented both sacrifice and elevation to a higher existence, allowing her to guide and protect her loved ones from afar.