Chan Sai-wah abides by his late father's word and marries the wealthy Yam Suk-kuen. They have a son, Kwok-leung. Though Wah is manager of the hotel owned by his father-in-law, Kuen is not a good wife. For all the years of their marriage, Wah has never been happy. Attracted to the humble and honest Carrie Mui, Wah decides to leave his domineering wife Kuen, but is stopped by his father-in-law. The lovers set off to Macau for a new start. Their life has become increasingly miserable under the pressure from Yam's family. When Wah leaves to seek help from his son in Hong Kong, Carrie decides she should leave so that Wah can go without feeling any guilt or burden. On the other hand, Wah is too ashamed to face his son, and returns to Macau. He lives his life in misery. Years pass, the lovers meet again. Wah is reduced to begging in the streets while Carrie becomes an opera diva.

Hak-ming heads the Ko Family, but he and his brothers, Hak-ting and Hak-on, and the second wife of the late Master Ko quarrel. Young Cousin Mui, who has tuberculosis, is forced by to marry an older woman. Kok-sun is guilty of being unable to stop the marriage. Sun and maid Chui-wan are wary of their feelings for each other due to class difference. Cousin Mui dies of illness. Hak-ting has his eyes on Wan. His wife, Wong, complains to their daughter, Shuk-ching, who cannot take it and commits suicide. Wong blames herself for her death. Undergone these tragedies, Cousin Kam's mother let Kam have a modern wedding with Kok-man. When Ming is ill, Ting and On want to sell the ancestral home. Hak-ming dies of angst. When the fifth uncle of Sun forces Wan to be his concubine, Wan tries to kill herself but is intercepted by Sun. Pressurised by people of the house over the issue of inheritance, Sun protests by declaring his love for Wan and leaves the family, with his mother, brother Man and Wan.

Ko Suk-ying is saddened over her arranged marriage as manipulated by her father Hak-ming. Ko Kok-sun's Cousin Chow Wai's spends the Mid-Autumn Festival before her marriage with the Kos. She has been in love with Sun. Sun finds out about her love for him when she is about to be married off, he is too weak to oppose to Wai's betrothal to another man. Sun's son, Hoi-sun, falls ill. Fearing the displeasure of his elders, Sun dares not consult a western doctor. Meanwhile, another dispute arises among members of the family over the ancestral land. When accused of being incompetent in his management, Sun takes the blame silently. Wai dies of grief while Hoi-sun becomes a victim of mistreatment. Sun is devastated at this double blow. Hak-ming instructs Sun to arrange for Ying's wedding. Knowing the kind of man Ying's fiancee is, Sun is reluctant. Not wanting to follow in Wai's footsteps, Ying fights for her own rights, and backed by an enlightened Sun, she leaves for a new start.

Kam Fan and Wong Ching-ping have a peaceful married life, until Ping's mother is serious ill. They desperately need a large amount of money. Fan tries in vain to raise money, he thus intends to use their daughter's school fees for the medical fees. Ping is against it and works as a song girl to earn money for her mother's medical expense. Her grudging husband Kam Fan uses a bed sheet to partition the bedroom into halves and even demands a divorce. After some mediation by their lawyer and neighbours, Wong finds a teaching job at an orphanage, but Fan still opposes it. Ping is so angry that she moves to live in the dormitory of the orphanage. Fan has to look after their daughter alone, making everything a mess. Later, their daughter catches a cold and has a high fever after an outing with Fan. Ping cannot set her mind at rest and goes home to take care of her daughter. The loving couple reconciles, for the sake of their daughter.

Cold Nights features great performances by both Pak Yin as a tough minded “new woman”, Shusheng, and Ng Cho-fan as her weak husband, Wang Wenxuan, whose spirits have been crushed by the Sino-Japanese war.