Sethu, Manu, Koshy and Varky are thick friends. One night after partying, they decide to go out to see a friend of Sethu who was leaving for US the next day. On the way they find out that someone has dumped the body of a girl in their car’s boot. Not sure what do, they kept driving thinking that they may find some way to dispose off the body. But they were soon stopped by Police sub Inspector Rajiv Kumar who found out that all four are drunk. On checking the car, Rajiv finds out the body of the girl. The girl’s body is immediately shifted to hospital in the police jeep while Rajiv started question the four friends. All four claimed that they know nothing about the girl. Rajiv was still suspicious and he threatens four of them that they may land up in jail for killing the girl. Rajiv then give an option to settle out the case for 10 Lakhs. The four friends agree and they give 10 Lakh in cash to Rajiv the next day afternoon. Thus the case was somehow brought to a closure
Three days later, Manu was stopped by Police while driving for using mobile phone. There he again meets the sub inspector Rajiv Kumar who issues a fine for him. But the Rajiv Kumar whom he met that day was different from the person whom four of them met 3 days earlier. Manu realized that they were fooled by someone – the Rajiv Kumar which all four of them met three days back was an imposter.
Manu comes back and discuss this with Koshy and Varky. They try to find out details on the girl whose body was found in their car. They come to know that the girl’s name is Merin Jose. They search for the girl’s details in Facebook and finds out that Sethu is one of her friends. They were shocked upon realizing that one among the four of them (Sethu) was actually part of the plot. How the remaining three friends go about from here and how Rajiv Kumar reaches the real culprit is the plot of Marupuram