Chettathi is a 1965 Malayalam language film. The film was directed by S. R. Puttanna Kanagal, starring Ambika, Prem Nazir, Sathyan and Thikkurissy Sukumaran Nair in the lead roles. Music of this film was done by M. S. Baburaj. It tells the story of a young widow. The core plot of the movie is partially inspired by Triveni's Kannada novel Hannele Chiguridaga.
Premachandran.(Sathyan) is the elder son of Master.(Thikkurissy Sukumaran Nair). Nirmala (Ambika) is his fiancée. Premachandran, who is working in a factory at Coimbatore comes home after a long time for their marriage. Prabhakaran (Prem Nazir) is Premachandran's younger brother who is in love with Vasanthy. After marriage, Premachandran returns to work, leaving Nirmala at his home. Nirmala takes good care of her father-in-law and brother-in-law and gains their love. Meanwhile, Premachandran meets with an accident at work and dies. This shocks the whole family. Gopi, Prabhakarans's colleague who is a womanizer develops a love interest towards Nirmala and proposes to her. But she declines. Prabhakaran's love and respect towards Nirmala is misunderstood by his father. Nirmala, with a broken heart, leaves home and joins her sister Susheela and husband Viswanathan. Prabhakaran, who refused to marry, gets married at the request of Nirmala. Prabhakaran gets uneasy with his wife's lazy attitude and he begins to complain, comparing each and everything with Nirmala. This creates a problem in his marriage life. Viswanathan approaches Nirmala with the wrong intention, but fails. He tells Susheela that Nirmala tried to entice him. Susheela asks Nirmala to leave the house. She comes back to her husband's home. There she overhears the fight between Prabhakaran and Vasanthy. Knowing that her presence creates problems with everyone's life, she leaves home. Master and Prabhakaran follow her, but they find Nirmala in a disturbed mental state. Soon Nirmala dies.