Farz Aur Kanoon is an action family drama. The movie revolves around a young couple - Inspector Ranjit Singh (Jeetendra) and his wife Bharati (Hema Malini), who live life with honesty and diligence. Ranjit dedicates his entire life in maintaining law and order. When the couple had their first and only son, Ravi (Raj Kiran), they were overjoyed and did everything for his happiness. However, things take a turn when Ravi embarks the life of crime and indulges in unlawful activities. Ranjit throws his only son out of the house, which immensely impacts Bharati, but she supports him. Will Ranjit’s efforts finally help him bring Ravi on the right track?