| Director | Mari Selvaraj |
|---|---|
| Box office | ₹52 crore |
Maamannan is an MLA belonging to the Dalit community, who rose up the ranks from being a cadre of the Samathuva Samooganeedhi Makkal Kazhagam (SSMK) in Salem district, Tamil Nadu. Maamannan's son Athiveeran alias "Veera", is an Adimurai practitioner who stopped talking to his father owing to emotional and physical trauma caused by a casteist attack from members of the local dominant community in his childhood. Rathnavelu is the SSMK district secretary for Salem and younger son of late ex-minister Sundaram, from a dominant community. Rathnavelu had fought a hard fight after his father's death, using all means available to reach the position of district secretary, despite not holding a public office. Rathnavelu's brash, aggressive behaviour often develops loggerheads with Maamannan.
Three months before elections, Rathnavelu's men destroy a free coaching centre run by Veera's friends and his love interest Leela because it was affecting the business of a private coaching centre run by Rathnavelu's elder brother Shanmugavel in his father's name. In retaliation, Veera and his friends destroy Rathnavelu's coaching centre. Rathnavelu realises that the issue might damage him inside the party and out, so he invites Maamannan and Veera to sort out this issue without further violence.
At the meeting, Veera notices that Maamannan is standing while everyone else including Rathnavelu are sitting in chairs. Veera asks his father to sit down, where Rathnavelu remarks that Maamannan will never sit down in his house and that has been the tradition since forever. Veera continuously demands that Maamannan sits down, Rathnavelu gets enraged where he slaps Veera and pushes Maamannan who intervened when his son is hit. An enraged Veera kicks down Rathnavelu in retaliation.
Rathnavelu directs his men to beat up Maamannan and Veera where he runs to fetch his gun, but his wife Jyothi locks him inside the room to prevent further chaos. Veera beats up all the men who attack him and his father, and they leave. Rathnavelu plans to counter-attack and kill Maamannan and Veeran but is ordered to stay put by the Chief Minister Ka. Sindhanai Rajan. Unable to attack Maamannan and Veera, Rathnavelu unleashes his dogs into the pigpen of Veera, resulting in the death of all except one pig. Veera, Maamannan, and their friends and family are deeply hurt by this symbolic cruelty.
Sindhanai Rajan orders Rathnavelu and Maamannan to come meet him at the Party HQ in Chennai. He asks Rathnavel to apologise to Maamannan or forgo the party membership. Rathnavel quits from the party and joins the main opposite party MSSMK (Marumalarchi Samathuva Samooganeedhi Makkal Kazhagam) with some of his followers. The sacking of a district secretary of the ruling party creates shock in the political scenario. Rathnavel nominates a candidate of his choice to compete against Maamannan, who is campaigning for a third term as an MLA. He even fields Jyothi in his place for another constituency to fully direct his efforts to defeat Maamannan.
Rathnavel challenges Maamannan that now that his support is not there, Maamannan will surely fail in the upcoming elections. A tight battle occurs during election campaign wherein Rathnavel tries to rally the support of all dominant castes against Maamannan. Rathnavel even kills a caste association head to create sympathy wave in favour of his candidate. All his plans succeed to some extent, but the youth of the constituency rebel against Rathnavel dictating whom each street should vote for. In the ensuing elections, Maamannan wins by a big margin and Rathnavel is left humbled and failed. The SSMK is re-elected to power, and Maamannan is made the Speaker of the Legislative Assembly. Veera and Leela continue to be engaged in their grassroot level social welfare activities.