Azhagar, the son of police constable Moovendhan, grows up under the shadow of his father’s impulsive, reckless behavior, which nudges him toward risky habits as he matures. He moves through life with a tight-knit circle of friends—A to Z and Iluppu Murugan are orphans, while Murugan himself grapples with a hidden drug problem. Sangu Ganesan, another friend, is separated from his family after his parents’ split. Azhagappan, fresh from college and the son of a hotel owner, provides financial support to his friends, strengthening the sense of a self-made, carefree unit that spends days loafing and nights drinking. The group also sides with two elderly allies, Chinnasamy aka Goripalayam MGR and a Retired Rowdy, who add a different flavor of street wisdom to their adventures.
In the meantime, Kazhuvanadhan, a veteran businessman, oversees two sons—Viruman, who revels in women and charm, and Karutha Pandi, who runs a usury operation and uses force to recover debts. When Azhagar’s elder brother nearly loses everything and tries to take his own life, Azhagar rallies his friends to chase down the thief and recover the lost money in Palanganatham. Their pursuit coincides with a brutal scene in which they witness a moneylender torturing a family, which spirals into violence when they stab one of the lender’s men who turns out to be a relative of Viruman. The moneylender then twists the narrative, painting Azhagar’s gang as the culprit behind Viruman’s sister, Viji. A misunderstanding grows when Karutha Pandi spots Viji with the gang and, mistaking her involvement, beats her.
Meanwhile, Azhagar’s personal life begins to collide with his sense of duty. He falls for Parvathy, the sister-in-law of his sister, and their families arrange a marriage for them. Yet after the wedding, Azhagar uncovers a painful truth: Parvathy loved Azhagappan all along. Realizing the mistake, he removes the thali and sends Parvathy to Azhagappan. This revelation enrages his family, who push him out of the house. As this family chaos unfolds, A to Z finds love with Poomayilu after a string of sour encounters, and their longing leads them to hatch a plan to marry by pooling money through a risky house looting scheme. They target a home they believe belongs to Viruman, but the plan goes awry; Viruman glimpses Azhagar’s face during the escape and, driven by rage and misperception, kills Viji.
The chain of violence intensifies when Kazhuvanadhan, seeing the gang, is knocked from his vehicle by A to Z, and dies. Viruman and Karutha Pandi vow brutal revenge, and Azhagar, along with A to Z, Murugan, and Ganesan, flees Madurai to seek safety. They hide first at Ganesan’s former mother’s place, then at Vijaya, Azhagar’s sister, where they endure humiliation. In the meantime, Azhagappan and Parvathy, now poverty-stricken after being ostracized by families, cross paths with them. Poomayilu reveals to A to Z that she is pregnant, adding weight to the couple’s risk-filled choices. With the danger looming, the friends decide to return to Madurai, hoping for a chance to set things right.
Parallel to these events, Retired Rowdy arranges for A to Z to marry Poomayilu, a union that would stabilize the group’s precarious fortunes. Viruman, not content with mere vengeance, hires a contract killer, Paandi, from Mathichiyam. Paandi’s backstory centers on his devotion to his younger brother Senthil and his own code of ethics, which grants victims a final wish. He arrives at the wedding with Viruman to wipe out the couple, and the night turns brutal: Paandi’s men capture Ganesan and sever his hand; Paandi himself kills A to Z. Poomayilu collapses in grief as her fiancé falls.
Grief and resolve push Azhagar, Murugan, and Ganesan back into confrontation. They plot to avenge their fallen friend by taking down Viruman and Karutha Pandi. First they strike Karutha Pandi, then, with the help of Rani, lure Viruman into a trap. After a brutal confrontation, they manage to bury Viruman alive, a grim resolution that marks a turning point in their lives. Azhagar, selflessly, arranges for Murugan to take care of Poomayilu and steps away from the immediate danger, focusing on the fallout of the violence and their lives ahead. He returns home to find his mother has died from jaundice, a loss that compounds the emotional toll of the year’s ordeals.
In the same breath of tragedy, Paandi appears at Azhagar’s doorstep with another mission in mind. However, faced with the cost of his violent life, Paandi asks for a moment to reflect, and, when that moment arrives, he kills Azhagar just as he mourns. The film then pivots to a sobering realization: Paandi’s own life begins to unravel as Senthil’s accidental death occurs before his eyes, revealing the hollowness of a path pursued through contract killings. This stark moment drives him toward reform, even as the weight of his choices lies heavy on the survivors.
The closing pages of the story see Poomayilu, Murugan, and Ganesan learning of Azhagar’s death and mourning the loss of their friend. Moovendhan, wracked with regret, recognizes that his lax parenting helped set this tragedy in motion. The film ends with Azhagappan performing Azhagar’s last rites, a melancholy but dignified closure that acknowledges the consequences of a life lived amid risk, loyalty, and unspoken love.
