Thanga Magan (1983)

Arun (Rajinikanth) is the haughty and belligerent son of rich parents Chidambaram (V.K Ramasamy) and Annapoorani (Manorama). Arun runs into constant tiffs with a pretty but combative hotel dancer, Chitra (Poornima Jayaram) and eventually they both fall in love. One night, when a hit-man Kali sent by his rivals attempts to murder Arun in his house and Chidambaram seems to recognize the hit-man and lets him escape, Arun confronts his father to know the truth. Chidambaram reveals to Arun that he is not his real son and years ago he and Kali had been deputed to kill the adolescent Arun and his mother by Arun's own father. But the kind-hearted Chidambaram had decided to adopt and raise Arun as his son. In another twist, Arun finds out that his real mother is Laxmi, an abandoned woman who had been living in Chitra's house. Arun is distraught when Chidambaram's version of the events of yore raise questions and doubts about a reticent Laxmi's past and morality. Laxmi later reveals to all how she had been deceived to lie in court of being immoral and later ordered to be killed by her criminal husband Velliangiri (Thengai Srinivasan) as a part of his nefarious designs to save his associate Rajalingam (Jaishankar). Velliangiri and Rajalingam who had in fact sent Kali to eliminate Arun, now aim to kill Laxmi as well when they learn she is alive. Arun battles to protect his mother and bring his criminal father and Rajalingam to justice in the rest of the story.