Mannar Mannan (Guru Somasundaram) is a villager who declares himself President of India. He leads many protests against various injustices happening around his village. Most of the time, he is seen as a joker. He and his small team of like-minded individuals sue on behalf of the villagers. One of Mannan's cases is against the local illegal sand mining group whose lorry maimed a goat. Another case is against a local school owner on whose property a toddler fell down an open deep bore well, resulting in brain damage. When this case was dismissed, Mannan stabs the school owner and is arrested. His past is told through the report submitted on the judge's order.

Mannan falls in love with Malliga, who is from the neighboring village. Malliga proclaims that she will marry him only if he builds a toilet at his home. He applies for a government scheme that provides incentive for building a toilet, along with his neighbors, but is cheated out of the government grant and is handed over just the basin. When the President of India announces a visit to the village to formally open the first toilet built under this scheme, Mannan's house is chosen. This prompts the village councilor to complete the unfinished toilet. It is still unfinished when the security team refuses clearance and another villager's toilet is chosen instead. Mallika yearns to use the toilet. When she does use it during a storm, the unfinished walls collapse on her and is discovered the next day by Mannan, the day of the President's visit. The police and the politicians lock him up in his house when he demands an ambulance. It was too late when Malliga is finally taken to the hospital. She goes into a vegetative state, and the foetus was lost. Mannan petitions all the way to the Supreme Court to grant euthanasia to his wife. He loses his mind while he waits for a verdict. He takes up various causes and is beaten in the police station every time.

Mannan gets out on bail to go to the final hearing in the Supreme Court. The justices deny the euthanasia petition and order a mental evaluation of Mannan. Mannan walks out of the hospital and hitchhikes his way back to his village. He is hit by a lorry of the sand miners. He is identified in the mortuary by his associates. Mannan's sister blames his associates for his death. In the end, the associates take care of Mannan's wife, while also reporting his death as a murder.