Surya, an introvert by nature, loves his classmate Priya from childhood but has never expressed his feelings towards her. Meanwhile, Surya's classmate Ajay also tries to woo Priya, in which he succeeds but to an extent. Priya does not like Surya as she views him as a nerd. One day, Surya gets frustrated as he is not being liked by anyone and cries loudly in a beach, where he finds a small idol of a God. He holds the idol, saying that it is better to be invisible rather than being disliked by everyone.

On returning home, Surya gets shocked knowing that he has really become invisible, while others can't see him but can only hear his voice. Surya's father is worried, as he is missing. Surya understands his father's love and discloses the truth to him alone. Taking advantage of invisibility, he always accompanies Priya without disturbing her. He also plays pranks on Ajay to exhibit his anger. Surya discloses the truth to Priya also following which she gets scared on hearing Surya's voice. Surya decides to rob a bank so that he could get some gifts for Priya, following which he gets media attention.

A special police team led by Tamizharasu and his assistant Singampuli is appointed to trap the invisible man behind the bank robbery. Priya informs the truth about Surya's power to Thamizharasu, and they set an eye on Surya to prevent him from committing further crimes. Despite attempts made by Thamizharasu's team, they are unable to stop Surya. Surya threatens that he will create problems in city if Priya does not love him. Thamizharasu comes up with a plan of using Priya to trap Surya and asks Priya to cooperate with the plan. Thamizharasu wants Priya to bring Surya to a deserted place which is already surrounded by police. Priya should talk pleasingly to Surya and in the meantime, should place her shawl over Surya, so that the police can trap him.

Everything progresses well as per plan. Surya comes to the place to meet Priya. Surya becomes emotional and starts describing his love towards Priya from childhood. He also explains certain events where Priya actually misunderstood him previously. On hearing these, Priya understands Surya to be an innocent and kindhearted person who loves her a lot. Thamizharasu overhears their conversation, understands Surya's good nature, and decides to trap him alive instead of killing. Thamizharasu instructs Priya to put her shawl on Surya, but Priya changes her mind. She informs the truth to Surya and pleads him to run away. Upon knowing the plan, Surya tries to escape, but suddenly it rains whereby revealing his presence because water droplets on Surya make others see it. Despite Thamizharasu's instructions, Singampuli shoots towards Surya, following which he dies. Priya cries seeing Surya's dead body, as she understood his good nature before his death.