Anniyan (2005)

Ambi, whose formal name is Ramanujam Iyengar (Vikram), is an innocent and honest lawyer hailing from an orthodox Iyengar family. He is very idealistic and goes out of his way to prosecute people who break the law. His obsession to abide by the rules and an expectation that everyone in the society should do the same, causes him to develop multiple personality disorder.

His normally docile personality gets taken over by two other personalities, a flamboyant model named Remo and a hooded vigilante killer named Anniyan. Remo takes over whenever Ambi is unable to woo Nandhini. Anniyan on the other hand is violent and deranged, and Ambi has no clue that such a monster exists within him. Anniyan kills lawbreakers by methods used for torturing people in hell, as mentioned in the Garuda Purana.

As law enforcement authorities investigate a series of gruesome murders seemingly the work of a single serial killer, Ambi's health deteriorates forcing Nandini, his girlfriend, to take him to NIMHANS, where he is diagnosed with multiple personality disorder. At NIMHANS, Ambi reveals to the psychiatrist (Nasser) his dark past: when he was 14 years old, he witnessed the tragic death of his 8-year old sister Vidya, due to civic apathy.

The psychiatrist concludes that the death of Vidya resulted in the development of this psychological disorder. He also triggers Anniyan and Remo and finds out that while Anniyan and Remo are fully aware that they are Ambi, Ambi has no clue about his multiple personalities. The psychiatrist then comes to the conclusion that while Remo can disappear if Nandhini accepts Ambi's love, Anniyan can only disappear if India is free from all its ills'. Nandhini eventually accepts Ambi's love and Remo disappears.

Will Ambi be forced to endure the punishment for Anniyan's crimes? Will treatment be successful in merging the disconnected personalities and allow Ambi to lead a normal and happy life with Nandhini?