Siva (1989)

Rajinikanth and Raghuvaran are close friends like their fathers, in spite if their difference in caste Hindu and Christian. However, in a cruel twist of fate, a villain brutally murders everyone in both families. Luckily, Rajinikanth, Raghuvaran and Raghuvaran's mother, escape with their lives. However, Raghuvaran is separated from the other two and is unaware that they are alive and vice versa. Two decades later, Rajinikanth falls in love with Shobana and marries her. The years have not been kind to Raghuvaran who has become hired goon, but will do only good deeds. Raghuvaran is hired to kill Rajinikanth and during the fight both get injured and finally they come to know that they are childhood friends. Finally, both of them unite and fight the bad guy who killed their family