A royal family is betrayed and tricked to death by hiding in a ventless-abditory by two subordinates, Sethupathi and Senathipathi. The sole survivor is the family's infant son, whom Sethupathi wants to kill, but Senathipathi convinces him to spare. Many decades later, Sethupathi's descendant, Chinnarasu, lives in a village. He is the son of Raasu Gounder, the incompetent head of the
village panchayat, and his long-suffering wife, Parimalam. The only son of the family, his father despises Chinnarasu, who dotes on his daughters. After Chinnarasu disobeys his father and competes in a
kabaddi game, they throw him out of the house. Chinnarasu returns drunk and belligerent and demands a share of his ancestral property from his father. Raasu Gounder spitefully gives him the deeds to the royal family's palace that Sethupathi killed. It is a place where they warned the family never to go to. While travelling there, Chinnarasu had an accident, becoming a delusional amnesiac. Meanwhile, Senathipathi's son runs a psychiatric hospital named after Senathipathi. Senathipathi's granddaughter, Sumitha, works as a psychiatrist at the hospital. After his accident, Chinnarasu is admitted to Sumitha's hospital and named Paandi. As Paandi, he befriends fellow patient Burfi and falls in love with Sumitha, who sees him only as a harmless but delusional patient. One day, Sumitha's father gives her a ring that once belonged to her grandfather. After Sumitha's mother puts the ring on her finger while asleep, Sumitha is strangled at night by the ghosts of the royal family her grandfather helped to murder until the ring slips off her finger. The next day, someone steals the jewellery from Sumitha's bag by the attendant of a sinister female patient. But Paandi takes it from her soon after, believing that the ring is an engagement ring Sumitha has bought for him. The ring is then confiscated from Paandi by a nurse and once again stolen, reaching the female patient. The female patient bargains with the ghosts, revealing herself as a sorceress named Neelakandi. She tells them that she will help them take revenge against Sethupathi's and Senathipathi's descendants in return for helping her resurrect her dead lover by sacrificing Sumitha on the night of an eclipse. Meanwhile, Thiru Don Sekar and his gang decide on a plan. They are going to kidnap Sumitha and then demand ransom from her father. On the eclipse night, Paandi and Burfi hide in Sumitha's car to smuggle themselves out of the hospital. When Sumitha leaves the hospital, Thiru Don and his gang successfully snatch her but accidentally make their ransom demand to Paandi and Burfi instead of Sumitha's father. They drop off an unconscious Sumitha for the ransom at the drop site but are angered to find the "ransom" in a rubbish pile. When they return to look for Sumitha, they see Neelakandi's ghost army kidnapping her and taken to the royal family's palace. But they believe the ghosts are another gang of kidnappers in disguise. Thus, the paths of Neelakandi, the dead royal family, Paandi and Burfi and the kidnappers coincide at the palace. When the kidnappers realise that the ghosts are dead, their attempts to escape the chateau and hilarity ensue due to Paandi's and Burfi's delusions and lack of concern about the ghosts. Meanwhile, Raasu Gounder and Parimalam visit the castle and are offended by their son's refusal to acknowledge them. At the same time, Sumitha's father enlists a priest to help rescue her from the palace. Upon their arrival, the dead king recognizes Sumitha's father as his youngest son, and the family switches sides to rescue Sumitha. The priest sets up a ritual to protect Sumitha during the eclipse, but Burfi destroys it and misunderstands it as Paandi's wedding, which no one invited him to. As Neelakandi begins the ritual, the priest empowers Paandi to fight against her evil powers and then tricks Neelakandi into believing that Paandi is the reincarnation of her dead lover. When Neelakandi embraces Paandi, the priest releases the soul of Neelakandi's lover, who is enraged by her apparent betrayal and kills her. The eclipse ends soon after, and the priest revives Sumitha and rescues her. == Cast ==