Oomai Vizhigal

A group of college girls arrive in a light blue matador at Chola Picnic Village and book a hotel room with a picnic spot. They spend the evening at the beach, light a bonfire, and sing and dance together. Vasanthi separates from the group, discovers the pi-shaped bell stand, rings it three times, and is abducted by P.R.K riding a carriage.

The next scene follows Raja as he enters the Chola Picnic Village to document the events. He photographs the pi-shaped bell stand and notices a beldam sitting beneath it. He then encounters a priest, introduces himself as Assistant Editor for the Dhinamurasu Magazine, and asks about the girl found near the village beach; the police call it a suicide, but the priest refuses to answer, and Raja files away another cryptic clue with his camera.

Lakshmana, the younger brother of P.R.K., shows up smoking and unsettles the scene. Raja extends his investigation but soon withdraws to pursue other leads. The village atmosphere thickens with danger as family ties intersect with the case.

Chandran and Raja develop the photos and realize they have a source inside the suspect's house in Uma, a stenographer. They identify MLA Sattanathan as the principal suspect. Uma overhears a phone conversation between P.R.K and the MLA about the Picnic Village inquiry, complicating MLA's position and widening the stakes.

The next morning, an inspector questions why the newspaper is pursuing the investigation, and Chandran defends the angle of the story. Vijay joins the magazine to help with the case. Raja and Vijay stay at Devi's house for rent, and Raja later brings Uma's blind father to live there, while Devi remains nearby; Raja notes he needs two to three days for clarifications.

Uma's birthday arrives and she is killed by MLA Sattanathan in front of Raja, shocking him and accelerating the case toward a formal investigation. The brutal act pushes the matter into the hands of DSP Deenathayalan. The personal tragedy connects the lovers—Raja with Uma and Vijay with Devi—in a web of betrayal and danger.

A newly married couple, Ramesh and Shanthi, honeymoon at Chola Picnic Village while being watched by the beldam. As the Maamarathu poo song ends and night falls, P.R.K storms into their hotel room and renders Karthik unconscious. The village darkens with imminent danger for the unsuspecting couple.

Shanthi escapes with the help of a passerby whose car stops to assist her. The passerby drives her to a hospital, while P.R.K opens the village gate and moves to kill her. The passerby also informs Vijay that a girl found undressed near the village has been admitted to a hospital, broadening the search.

Raja arrives to help Shanthi, but a member of Sattanathan's gang hides in Shanthi's room to ambush her. Raja emerges in time but is stabbed by the thug; he fights back, kills the attacker, and carries Shanthi to the DSP's house before dying there. The scene cements the personal toll of the conspiracy.

Peter, Ramesh, and Vijay join forces to uncover why P.R.K acts this way and to connect the disparate threads of the case. They pool resources and pursue leads that reveal the depth of the scheme. Their collaboration marks a turning point in the pursuit of justice.

P.R.K gathers the remaining players and reveals his fixation: he loves eyes and plans to take them from the girls he sees. He explains that his stepmother, the beldam, feeds him information about each victim, guiding his actions. The confession exposes a twisted, familial motive at the heart of the crimes.

DSP Deenathayalan deduces the truth and punishes the conspirators for their crimes. Ramesh and Shanthi reconcile as the ordeal concludes, and the village confronts the consequences of the respectability and corruption that fueled the killings. The survivors begin to heal as the case closes.