As it is revealed later in the film, Gayathri had not died but had merely passed out. Gautham, in his hypnotic state, swears furiously to Rajashekar that he will avenge Gayathri's murder by capturing and killing the three men responsible. The way Gautham remembers it is - the three men had molested and murdered Gayathri and then had left Gautham for dead after striking him on the head. In the ensuing fight, Balaji's knee was struck with an axe, Gayathri dropped unconscious, and Gautham was hit hard on the head with the blunt end of the axe. Hearing her screams, Gautham and his friend Balaji attempted to rescue Gayathri. Then, one day, the three men got drunk and began molesting Gayathri. Gayathri regularly ran up to Gautham to seek refuge from the men's pursuits. Gayathri ( Kaveri) was a local girl who was teased frequently by the three men.

While in that trip, he encountered three men - Prakash (Shajin), Soundar ( Ponvannan), and Shanmugam ( Thalaivasal Vijay) - who all hailed from Pondicherry. About six months earlier, he had traveled to a hill resort in Tamil Nadu for his research on musical patterns in the sounds of nature. It is revealed that Gautham was actually a musicologist. Rajashekar ( Raghuvaran) is a psychiatrist who discovers Gautham's real condition and the dangers it poses. The group members are initially hostile to him but eventually decide to help him after Gautham pursues them aggressively and Hema realizes that he may be suffering from a neurological condition resulting in amnesia and delusions.

He encounters a group of friends headed by Hema ( Shalini) and requests their help in locating Gayathri ( Kaveri), who appears to be Gautham's lover. The film opens to Gautham Prabhakar ( Vijay) searching all around Pondicherry in vain for a girl named Gayathri. The film is about a person who suffers from a neurological condition that results in partial retrograde amnesia and delusions due to a head injury and his subsequent recovery thanks to a kind girl and her psychiatrist father.

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