Fong Sum

The agile and cerebral fighter Kong Yin is invited to join the police SWAT team. Kong is soon sent on an undercover mission to investigate the gang operating at the Happiness Rubber Plant to coerce female workers into prostitution. An indignant Kong joins hands with fellow worker Chow Mei-ha and factory head Wong Chi-kong to expel Blackie Kei whose ruthless and blatant exploitation of the workers has been going unpunished. Facing the loss of a lucrative source of income, Blackie and his underworld bigwig boss Wu Tin-hung intercept the love letters exchanged between Wong and the wife of the general manager Ting Yuk-lan and use the correspondence to extort money from the adulterers. The fearless Chow dons a maid disguise and ingratiates herself with the gangster, followed by a police raid masterminded by Kong to crack down on the notorious gang.

Wan Cho-sin has two daughters. The elder sister Wai-man is genteel and graceful, and the younger sister Wai-ping, taken under the tutelage of Lady Knight Silver Fox, is extrovert, outgoing and gregarious. The drug kingpin Chung Chi-wang has his eyes set on Wai-man but the girl is in love with Ma Kim-leung. Ko Tin-yam, who fearlessly wields his journalistic pen against the gangster, joins forces with his girlfriend Wai-ping to beat off Kong Yau-ming and the thugs dispatched by Chung. The encounter, leads to Kong's recognition of Wai-ping as his flesh and blood entrusted to Cho-sin's care years ago. Wai-ping pleads with her father to turn over a new leaf but fails to save him from Chung's murderous hand. Wai-man and Ma ingratiate themselves with the gangster, who uses the duo to elude the police while transferring drugs to a secluded villa. Wai-ping tips off the authorities about the traffickers' whereabouts and cracks down on the drug ring.

The blind Yip Man-chiu was abandoned at birth. Following the death of his foster parents, the boy is sold by his uncle Ah Sam to a blind Taoist priest, an abusive man. Running away from home, Yip is hit by a car and sent to a school for the blind by the social security workers. His talents impress the musician Siu Kwong and wins him a place in a music school for the blind. There he is joined by fellow students Lung Kwok-kei, a runaway child with an abusive stepmother, Chow Kuen, an abandoned child found on a train, and Cheung Kin-ching, an avid music lover sent to the school by her loving well-to-do father. The four children blossom into accomplished musicians under the tutelage of Siu and his wife and together with the less fortunate others, form an orchestra which earns a reputation for excellence.

In high society there is a Madam Rose. Shum Chung-kei meets her and is enthralled. They begin dating. Kei knows very little about Rose. When Rose was little, her father Fok Wing-sum was betrayed by his business partner Shum Hung, who made him lose all his money. Hung was put in jail. Years later, when the Sino-Japanese war broke out, Hung reappeared as a spy. He arrested Sum. Although Sum escaped later, Hung caught his wife, who died later. Madam Rose wants to find Hung's offspring to take revenge. When she confirms that Kei is Hung's son, she approaches him. They are getting married. Kei invites his father to the wedding. Rose and Sum are anxious. However, Hung is alert and comes quietly. He discovers who Rose is and her motives. Rose and Sum go to Hung and they fight. Hung is guilty. He tries to jump off a cliff. Sum saves him. The enmity disappears. Kei and Rose stay together.