1986: Sethupathi is a gangster in Madras who has a gang of 100 goons, working as vigilantes. One day, Sethupathi's enemy's barge into their house to kill Sethupathi, but Annalakshmi goes into labor. The gang beat the intruders while Sethupathi is with his wife.

Annalakshmi gives birth to a boy but dies. Sethupathi goes to his wife and gives the boy to his gang member Mansoor, who names him Vikram aka Sulthan. The gang raises Sulthan with love and care, and Sulthan sees them as his brothers. Sulthan grows up and goes abroad to pursue Robotics Engineering.

2021: A village head meets Sethupathi with a request to kill a person named Jayaseelan. The head narrates about the village practices in agriculture. When Jayaseelan asks for their land, they refuse which enrages him, and he kills many farmers and burns their lands. Upon hearing this, Sethupathi promises to kill Jayaseelan.

When asked by Mansoor, Sethupathi tells that they have done many crimes in their life and they can do something good with the case of the head. At the same time, Sulthan arrives at the village in great splendour. One day, the gang is attacked by a few people who pose as pizza delivery men. They injure Sethupathi and a member of the gang, who is critical and admitted to the hospital.

The goon's mother is distraught, leaving Sulthan mentally tarnished. Sulthan angrily confronts Sethupathi and tells him that he is going to leave and never going to come back. Due to this, Sethupathi dies in his sleep. At Sethupathi's funeral, Sulthan finds out that the attackers that night are police officers sent by Commissioner Manickavel with the intent to kill Sethupathi. Sulthan meets him and asks for an opportunity to reform the gang.

Manickavel gives Sulthan 6 months to reform them, but tells him that not a single case should be filed on them in that time. Mansoor gets a phone call from the village head reminding him of the promise made to them. Mansoor sends twenty of the men including Otta Lorry to kill Jayaseelan, but Sulthan forbids them. They try to sneak out to the village but Sulthan catches them. Otta Lorry comes up with a lie that he has a marriage proposal in the village.

Sulthan decides to take the entire gang with him to the village, so they will be out of trouble. The entire village goes along with the lie with a promise made by Mansoor saying that they will kill Jayaseelan. The head's daughter Rukmani acts as the bride. Otta Lorry rejects her as an act, but Sulthan genuinely falls for her. He confesses his love for her to the family and asks for her hand in marriage but she rejects him.

Sulthan tries to woo her but to no avail. The gang wants to leave, but Sulthan tells them that until Rukmani falls in love with her they will not leave. The gang secretly follows Jayaseelan planning to kill him, but their attempts are unsuccessful. The village finds out that Jayaseelan is not after their lands but rather for the iron in a mountain. The only way to stop Jayaseelan is to prove their lands are fertile and that crops can grow on the land, but they only have 6 months.

Sulthan is reprimanded by Rukmani while Mansoor and the gang attempt to kill Jayaseelan at the market, but Sulthan who is in the market stops the attack and yells at the gang. As they prepare to leave, a villager informs the gang that Jayaseelan has taken over the city. Jayaseelan brutally beats all the villagers including Rukmani. An angered Sulthan severely beats up Jayaseelan and his men.

Meanwhile, the police force starts a sting operation to kill all the goons in the city in unofficial encounters to attain peace. Sulthan learns about the news and extends their stay in the village for 5 more months and in their stay, they will practice agriculture. They work day and night in the fields. A corporate businessman arrives at the village and asks Sulthan if he can buy the mountain, but Sulthan refuses.

Enraged, the businessman sends goons at night to kill Sulthan but Sulthan beats all of them. The next day, Michael, one of the members of the gang, attempts to drown someone. Sulthan stops him and tells him to leave the group but later finds out that the man Michael was beating was assaulting a woman. Sulthan apologizes to Michael but he turns bitter towards Sulthan.

The gang's hard work is rewarded when their plants start to grow on their land. The businessman grows enraged after hearing the news, but Amith Raj, who is a part of the Ministry of Mines postpones the inspection so that the businessman can prove that the lands are barren. Rukmani reciprocates Sulthan's feelings and accepts the marriage proposal. Sulthan and Rukmani get engaged in front of the villagers and the gang in a grand celebration.

Sulthan buys 2 acres of land for the whole gang by selling his house and spending his entire saving. That night on the bus, Mansoor gets fatally stabbed by a few people sent by the businessman, but Sulthan beats all of them. Mansoor dies due to his injuries. The gang gets ready to go and kill the businessman but Sulthan stops them. Michael challenges Sulthan to a fight and whoever loses should follow what the winner tells them to do. Sulthan manages to overpower Michael but this leads to the gang loathing him. The gang leaves Sulthan and leaves the village, leaving Sulthan devastated.

The businessman learns that the gang has left Sulthan so he plans to burn the village. Jayaseelan calls Sulthan and tells him that he brought many people to kill Sulthan and the villagers, and they will be coming back. Sulthan decides to protect the village from Jayaseelan and the businessman. Sulthan evacuates all the villagers from the village, but he stays back to protect the village. The businessman and his men arrive at night and burn the crops but Sulthan, his guard Gada and a few farmers arrive and kill many of the businessman's henchmen, but Sulthan gets injured.

Sulthan beats up and kills the businessman and his men. Just then, Jayaseelan and his men arrive with a kidnapped Rukmani, but the gang arrives, when they learn about Sulthan's sacrifices to protect them, and Michael apologises to Sulthan. They reconcile with Sulthan and they kill Jayaseelan and his men. The gang begins to work again in agriculture willingly while Sulthan and Rukmani watch on.