Director: K. Balachander; Producer: R. Venkataraman, S.S. Nachammai, K. Arumugam, H. Nagaraja Rao; Cinematographer: N. Balakrishnan; Editor: N.R. Kittu; Cast: Gemini Ganesan, Nagesh Babu, R. Muthuraman, Jayanthi, S.V. Sahasranamam, M.R.R. Vasu, V.S. Raghavan, S.V. Ramadas, I.S.R, Sasi Kumar, A. Sakuntala, Nalini, Kalavathi, Shoba, S.N. Parvathy, Baby Mythili, C.S. Pandian, Veera Raghavan, Karikkol Raja, K.K. Soundar, Chandran, Thangaraj, Natti, Dhanapal, Parandaman, Balu, Rajavelu, Suryakumar, Parthipan, Seetaraman, Anandan, Sekhar, S. Umapathi, Major Sundar Rajan, V. Gopalakrishna
Duration: 02:33:59; Aspect Ratio: 1.363:1; Lightness: 0.271; Volume: 0.236; Cuts per Minute: 12.552
Summary: Sathya (Gemini Ganesan), Rajan (R. Muthuraman), Rajbabu (Nagesh), Mandiramoorthi (M. R. R. Vasu) and Haniff (V. Gopalakrishnan) are friends who graduate from the same college. In order to celebrate it, they go on a drive around Madras in Haniff's car, singing about the then ideals in life. The car crashes and Haniff dies, leaving his friends shocked. Rajan, Rajbabu and Mandiramoorthi later succumb to corrupt lifestyles while Sathya vows to remain a righteous person. He meets a young women Kanchana (Jayanthi), who has been seduced, raped, impregnated and abandoned by a playboy (S. V. Ramadoss). She gives birth to a son Kumar; Sathya marries her, knowing about her history and raises Kumar as his own. The playboy meanwhile, leaves his wealth to his illegitimate son, but Kanchana rejects it. In the meantime, Sathya's kidneys are affected and all of his friends walk away when the doctor asks them of any of them would donate their kidneys for their friend. In the end Sathya dies, his wife realises that she has successfully up held the values that her husband had taught her. The story is narrated by Rajbabu, who wants to write a book and requests his rich friend to get it published. All these sequences are narrated by him and acted by the artistes as chapters of the book. Finally, Sathya's friends realise their folly and bring out the book with the title as Punnagai.