Vasanth, a stock analyst, and his wife Malini Meena search for a flat in Chennai and soon settle on a striking unit on the 12th floor of a tall building. The purchase seems perfect at first glance, but the apartment carries a dark and unsettling history. The previous occupant, Manju Meena, killed her child and then hurled herself from the balcony, a tragedy that is quickly woven into the couple’s new surroundings. As Malini delves into the story, she grows oddly fixated on what happened, and her behavior starts to shift in troubling ways. What begins as curiosity inches toward something more disturbing, and Vasanth begins to fear that his wife may be slipping into a psychological disorder.
To navigate his creeping doubts, Vasanth consults Dr. Rajan, a psychiatrist, hoping for rational explanations and reassurance. Yet the unsettling events surrounding the building keep piling up: a watchman is found murdered with the head twisted in a brutal, inexplicable manner; a resident named Ajay behaves erratically; and another murder shakes the community. The town’s investigators take an interest, with Inspector Paramasivan Thyagarajan leading the inquiry, trying to piece together the seemingly disconnected incidents.
The tension intensifies when the maid, convinced that Malini is possessed, calls in an exorcist Suhasini Maniratnam. The exorcist spends time with Malini and uncovers a chilling truth: Malini is indeed possessed, and the spirit inhabiting her is Manju. In a desperate bid for answers, Vasanth travels to Manju’s mother, whose help proves pivotal. With her guidance, the possessed Malini reveals a harrowing backstory: Ajay had lusted after Manju and forced himself on her, and in a bid to survive, she jumped from the balcony. But the plot thickens as Ajay discovers that Manju’s son witnessed the assault, and he coerced the watchman into throwing the child to the ground, fabricating a tale of a murdered mother and a suicide to cover up the truth.
Driven by the vengeful spirit within Malini, Manju seeks vengeance on Ajay, and the plan unfolds with dramatic consequences. The excruciating truth comes to light, and a turning point arrives when Manju’s mother intervenes, explaining that vengeance cannot be achieved by turning Malini into a murderer. With that intervention, the possession begins to lift, and Manju withdraws from Malini’s body, signaling the end of one cycle of fear and retribution. Ajay is exposed and dragged before the others, his fate sealed in the public eye.
The aftermath settles into a grim resolution: Ajay is sent to prison, condemned by the weight of the revealed truth and the law. Paramasivam, steadfast in his duties, insists that Ajay must face the consequences and rot in his jail cell. In a final, unsettling moment, as Paramasivam leaves the cell, Ajay confronts the haunting memory of Manju. He pleads for mercy, but the atmosphere turns spectral as Manju’s presence closes in; the scene fades on a chilling implication that she claims him, leaving his fate ambiguous and echoing the film’s themes of vengeance, guilt, and the supernatural.
