Jayarajan, Mohanlal, an over-enthusiastic assistant manager at a tea plantation, hatches a bold plan to loot a massive sum from the company. He lures two debt-ridden subordinates, Chandran and Johnie into his conspiracy. Though initially reluctant, they agree. But during their attempt, A. K. Menon, Janardhanan, the manager of the company, catches them red-handed. To keep matters under wraps, Jayarajan enters Menon's house at night, asking Johnny and Chandran to wait outside, claiming that he would negotiate with Menon. Jayarajan kills Menon and escapes from the house. He acts normal the next day and provides help to the police. But both Johnny and Chandran feel guilt to the soul. Jayarajan says he will keep silent and act as if nothing happened.
Soon, however, Jayarajan is elevated as the new Manager of the company. Devi, Kaajal Kiran, the fed-up young widow of Menon, due to Menon's negligent behaviour towards her, arrives at the plantation for terminal financial formalities. Jayarajan, who already was having an affair with the money-motivated Padma, a nurse of the Plantation Hospital, now eyes Devi. He succeeds in seducing Devi and having sex with her after which he plans to siphon off all the financial benefits that she might get as Menon's bereavement benefits. But a cop, Inspector Ravi, Ratheesh, becomes suspicious of Jayarajan, although he has nothing to nail on Jayarajan, due to the flawless and naturally responsive demeanour of Jayarajan.
Cop Ravi starts investigating Jayarajan's past and finds some loose ends, but he gets no solid proof in this regard. But Ravi keeps a watch on Jayarajan. However, Jayarajan neither stops his illicit relationship with Padma the nurse nor deserts Devi. In a strange turn of events, fearing faint-hearted Johnny might spill the beans of the Manager's murder, Jayarajan finishes off Johnny in an orchestrated jeep accident and Padma, by strangulation, mimicking a suicide without any trace of suspicion about the two murders to anybody except Chandran, whose silence Jayarajan buys with scare tactics.
Meanwhile, the elderly owner of the estate visits the plantation. Knowing that his young daughter Vasanthi would inherit the company, Jayarajan tries to woo her too. But Devi becomes a hindrance in his plans and her insistence for a marriage pushes him to plot a plan to finish off Devi too. But before he can kill Devi, Chandran informs Vasanthi the truth about the death of Menon and both succeed in calling the cops. But before getting arrested by Ravi, Jayarajan jumps down from the heights and commits suicide.
