Saani Kaayidham

In 1989, Ponni dedicates herself to ensuring Dhanam's education and a responsible future for her family. Maari, a mill worker, dreams of challenging caste barriers by entering local politics. Their ambitions put them at odds with the powerful mill owner and his relatives, setting the stage for a confrontation.

Maari retaliates by humiliating Perumal and his relatives, sparking a cycle of resentment. The act deepens the fault lines between the working family and the upper-caste landlords. The village atmosphere grows tense as old enmities flare up.

Perumal and his relatives burn Ponni's house while she, Maari, and Dhanam sleep inside. They later lure Ponni with a false pretence and sexually assault her, but they leave her alive, knowing her status as a policewoman could trigger legal trouble for them.

Ponni pursues justice in court, but the culprits use their influence to secure only a minor sentence. The verdict reinforces the sense of injustice and motivates Ponni to take matters into her own hands.

Reeling from the assault, Ponni swears revenge and teams up with her half-brother Sangayya, who shares a bitter history with the upper-caste landlords. The alliance marks a turning point in her plan for retribution.

Ponni and Sangayya reconcile after recognizing a shared burden and a bond formed through Dhanam. Together, they commit to pursuing justice for what happened that night.

The duo finds Rani in an abandoned building and Ponni confronts and eliminates her as part of their plan. They also uncover the locations of Perumal's men and prepare for further action.

Ponni and Sangayya torture Anbu and finish him, pushing the search for the gang deeper. The act demonstrates their ruthless resolve to dismantle the criminals' network.

Perumal comes under pressure as his younger brother Giri, who had aided the group in hiding, pursues him due to an inheritance dispute. Giri loses his life in the ensuing conflict, altering the power dynamics.

Sudalai, Dhanam's close friend who survived the fateful night, is kept safe at Ponni's insistence that he was not involved. Sangayya takes Sudalai to a hiding spot as the danger closes in.

Sangayya burns a lodge and abducts Vasu. Ponni then pours acid on him and brutally ends his life, continuing their campaign against the perpetrators.

Ponni uses a van to ram into Giri and his henchmen after one of the goons stabs Sangayya, with Giri narrowly surviving the ambush and escaping.

The last targets, Maini and Deva, are tracked to a cinema theatre. Sangayya hacks off Maini's hand and decapitates him, while Deva is killed by Ponni and Sangayya’s ongoing assault.

Giri arrives with reinforcements, but Sangayya sacrifices himself by blowing up the van with gas cylinders, killing the reinforcements and Giri in the blast. Ponni is left devastated by the loss and the violence she has unleashed.

After a period of recovery, Ponni departs with Sudalai, learning that Sudalai was innocent of the assault. The cycle of vengeance closes as she steps into a gentler future with her nephew.