Jin Tieyi has been learning martial arts from his master Zhang Tianxi since he was a child, and has practiced martial arts with Tianxi's children Wenlan and Daxiong. One day, Tieyi followed his master's order to travel around the world. On the way, he was attacked by corpses in a strange temple. Fortunately, he was saved by the Taoist Leng Tianhun. Tianhun and Tianxi were enemies, so he pretended to accept Tieyi as his apprentice and use him.

Chor Yuen started his directorial career with a bang. From its very first image, The Natural Son establishes Chor as a filmmaker of stylistic flourish, which would be sustained in various forms throughout his long tenure. Adapted from '30 cents' pulp fiction, it is a Kong Ngee melodrama made in the studio's mould, with Westernised characters and trendy middle-class lifestyles. Yet, Chor's first film is not exempt from the social urgency that characterises the Cantonese cinema of his father, Cheung Wood-yau. The film cloaks its entertainment in a moral deliberation on blood ties, its story about the raising of a bastard child a head-on challenge of archaic family values. An ostentatious start for a colourful and eventful career.

The film focuses on a mother (Chen Yanyan) burdened by guilt after abandoning her newborn daughter in a long lane 17 years earlier, so that she could adopt a son to fulfil the traditional belief that only a male heir could continue the family line. However, when her adopted son (King Hu) becomes a disappointment, the mother’s regret deepens. On her deathbed, she confesses her secret to her husband (Wang Yin), who resolves to find their lost daughter.

This script was adapted from a Rediffusion Radio airwave novel, written by Lang Wun and read on-air by his wife Ngai Mun. Ngai Mun also acted in this film. Wang (Cheung Ying) worked himself to an early death. His wife Ching (Hung Sin Nui) raised their three children all by herself. Eldest son Kei (also played by Cheung Ying) was spoiled and grew up to be a robber. Middle child, daughter Ching-han, is materialistic and vain, and is later killed by Kei. Youngest son Leung (Yeung Fan) is diligent and ambitious, a great comfort to Ching. Hung Sin Nui played Ching from a young to an elderly woman, showing off her practiced, perfect acting skills. Chun Kim’s detailed portrayal of the relationship between the two generations set the stage for his later work Parents’ Hearts (1955).