Devotion: The Sins of the Father tells the story of the troubled screenwriter Du Feng Yu (杜豐于) through a Taipei apartment complex with rooms that represent various years in the lives of the Du family during the 1980s. The family consists of Feng Yu, his wife Gong Li Fang (鞏莉芳), a retired songstress, and their daughter Du Mei Shin (杜美心), an aspiring child singer. Feng Yu's screenwriting career has stagnated while Mei Shin begins to show signs of a mysterious illness. As the family's financial situation deteriorates, Li Fang has frequent arguments with Feng Yu about whether she should come out of her retirement to help support the family. In the midst of the domestic disputes, Mei Shin enters a popular singing contest, seeking to please her parents by becoming a popular singer. However, Mei Shin's performance of her mother's signature song "Lady of the Pier" (碼頭姑娘) comes one point shy of advancing to the next round. Mei Shin's condition worsens after the setback, to the point she's unable to sing. Despite a doctor's suggestion that the family seek psychiatric care for Mei Shin's illness, Feng Yu instead begins to follow the teachings of cult leader Mentor Heuh (何老師) regarding the folk deity Cigu Guanyin (慈孤觀音), who could supposedly help cure his daughter and her singing career. When Feng Yu becomes increasingly obsessed with Mentor Heuh, Li Fang attempts to convince her husband to snap out of his obsession, but Feng Yu accuses her of being possessed by evil spirits. Realising her husband will not listen to her, Li Fang eventually leaves the family. Seeing the downward spiral of her family, Mei Shin asks her father to help her fold origami tulips, believing that she will be healed when enough has been folded to fill her room. Instead, as instructed by Mentor Heuh after a séance, Feng Yu performs a dark ritual by submerging his daughter in a bathtub filled with rice wine and banded krait and locking her up in the bathroom for seven days, assumedly causing her death. Though Devotion is just a fiction but it also represents the tragic stories of many children raised in Asian countries when Patriarchy and Superstition still exist. Devotion is even more tragic when the head of the family is both patriarchal and superstitious.