Both top actors in Hong Kong films, Stephen Chow and Lau Ching Wan started their illustrious careers at TVB playing bit parts and supporting roles in the 1980s. Their profiles gradually went on the rise, and the 1990 drama series It Runs in the Family was the first and only screen team-up for the two then-rising stars. It would also be Chow's last starring vehicle at the No.1 TV station in Hong Kong, as he would turn his focus to films after this. The charismatic duo share top billings in the comedy series as twin brothers separated at birth and leading very different lives. Wong Ming Shing (Lau Ching Wan) grew up with his wealthy mother, while Wong Lei Chau (Stephen Chow) was adopted by a vulgar house decorator named Lo Fai (Leung Ka Yan) and had his name changed to Lo Sai. Years later, Shing has become a hotshot film director, and by pure chance he finds himself living under the same roof with Sai without knowing their real relations. The brothers get entangled in a romantic triangle when Sai's childhood sweetheart Kar Nam (Amy Chan) begins dating her superior, Shing. Meanwhile, Fai meets Kar Nam's aunt and begins an unlikely romance with her despite their difference in social standings. Shing and Sai/Chau eventually find out that they are twins, but could that bridge the substantial personality gap between them?
Another touching comedy after The Justice of life, characterized by a delightful storyline and amusing lines!
The story runs on a pair of separated twin brothers, Wong Ming-Shing (Sean Lau) and Wong Lei-Chow (Stephen Chow), with Shing living with his mother and Chow adopted by Lo Fai, a poorly educated decorator who named him Lo Sai. As time passes, Shing becomes an avant-garde film director, astute, courageous and full of brilliant ideas, while Sai an agreeable and upright man working as a resourceful broker. By chance, the two brothers meet and share an apartment without knowing of their bond as brothers and are later drawn into a love triangle by Sai's dream girl, also his childhood friend, Ka-Nam (Amy Chan), who had fallen for her supervisor Shing.
After a reunion as brothers, Shing and Sai remain estranged due to their differences in personalities. But when Shing is amid a prosecution, the brotherhood instinct in Sai with the help of family and friends spares no rescue Shing.