The Daoist philosopher Zhuang Zhou retreats from political life to live in seclusion, while his wife, Lady Tian, grows resentful of their humble existence, envious of their friend Hui Shi’s illustrious career. To test her loyalty, Zhuang Zhou feigns death by drinking lacquer tree poison, later reappearing as the dashing young nobleman from Chu. Torn between the ethical shackles of widowhood and the allure of newfound passion, Lady Tian ultimately wields a sword to split Zhuang Zhou’s coffin, seeking his "marrow" to save the "poisoned" young nobleman—only to accidentally revive her husband.

When the truth is revealed, Lady Tian takes her own life in a final reckoning with love’s essence, forcing Zhuang Zhou to confront his own cowardice in orchestrating the cruel test. The play concludes with Lady Tian transforming into a butterfly amid flames, while Zhuang Zhou drums on a basin and chants, realizing that all earthly attachments—ambition, desire, even life and death—dissolve like a fleeting dream in the Daoist realm of "the unity of all things".