Director: Suresh Krishna; Producer: Kalaipuli S. Thanu; Cinematographer: S. Thiru; Cast: Kamal Haasan, Raveena Tandon, Manisha Koirala, Kitu Gidwani, Shri Vallabh Vyas, Milind Gunaji, Vikram Gokhale, Naveen Nischol, Smita Jaykar, Anuradha Hasan, Riyaz Khan, Mayilsamy, Major Ravi, Sarika, Yashpal Sharma
Summary: Vijay Kumar, an army commando in Delhi, is due to marry his girlfriend Tejaswini "Teju", a TV news presenter. Vijay's twin brother, Nandu, is a paranoid schizophrenic mental patient who has spent most of his life in an asylum for killing his abusive stepmother. Vijay cares about Nandu and looks forward to his release, but a doctor tells him that Nandu has developed into a psychopath. He is now a danger to society and should not be released.
Vijay and Teju visit Nandu to share the news about their impending marriage, which turns disastrous as Nandu begins to see Teju in the image of his stepmother. Seeking to save Vijay from Teju, Nandu manages to escape custody after killing two other inmates. He later meets his maternal uncle, who was responsible for incarcerating him. The uncle dies of choking upon seeing his nephew. After their marriage, Vijay and Teju are shocked to learn of Nandu's escape. Nandu's doctor believes it was another patient who escaped, but Vijay is convinced that it was Nandu. Nandu visits Vijay's home when he is not there and leaves a message about wanting to kill Teju. He keeps hallucinating about his deceased mother in his imagination. While searching for Teju, Nandu meets socialite Sharmilee and they both develop a liking for each other. Upon being drugged, Nandu hallucinates about Sharmilee as his stepmother and brutally murders her. Regretting his actions, he burns her corpse before exiting the room, but leaves behind evidence through which Vijay deduces him as the murderer. Vijay and Teju leave for Vijay's ancestral home in Ooty to stay safe from Nandu, but he secretly follows them. Vijay and Teju find Nandu's old diary in the house through which they read his past: Vijay and Nandu's mother committed suicide after finding out that Santosh, their father was having an affair with Jayanthi, who later becomes their stepmother. Both brothers hate her and Nandu becomes violent at school. The teacher complains about this and Nandu justifies that he is only reflecting the home environment. Enraged, Santosh beats both his sons for disliking his new wife. One day, the brothers learn that Jayanthi is having an affair with another man and Nandu tries telling this to his father who pays no heed, and instead beats him. Nandu pleads to his maternal uncle to take him along with him. But as he is suffering from throat cancer, he refuses and suggests a boarding school. Eventually, Vijay leaves with his uncle to a boarding school while Nandu remains home.
The situation gets worse at home with Nandu and Jayanthi turning violent and Santosh gets a heart attack. Nandu overhears a conversation between Jayanthi and a lawyer, and realises that she is only after his father's wealth. Seeing this, Santosh dies due to another heart attack. Nandu now starts to see both his deceased parents in his hallucinations. His mother gives him the mission of killing Jayanthi, which Nandu does. Nandu stays with the corpses in the house before being incarcerated at the asylum. In the present, Vijay learns from his old friend Thenkoshut that Nandu has reached Ooty. Vijay reaches on time to save Teju from Nandu, who entered their hotel room and leaves with her. Nandu chases the car in which they escape. After a long chase, Vijay manages to push Nandu's car into an abyss and assumes he is dead. However, Nandu escapes and continues his trail. Vijay plans to leave the city and notices Nandu coming to the hotel secretly. Vijay and his commandos try to nab him but he takes on everyone and kills many. Finally, the brothers have a fight where Nandu overcomes Vijay. He corners Teju who starts whacking him with a belt in self-defense, reminding Nandu of Jayanthi's manner of punishing him. Vijay reaches by then and there is another fight between the brothers. Nandu visualises his mother asking him to join her as Jayanthi is torturing her up there. He realises his mistake and apologises to Vijay for chasing Teju. To kill his stepmother, he lights up some cylinders which explode, killing him. Teju is later revealed to be pregnant with twins.