Plot
Krishnadas, a former SP of Kerala Police, has just retired and prepares to attend a send-off event arranged by his colleagues when a subordinate officer, CI Praveen, arrives to inform him that an IB report has warned against the arrival of a criminal. Upon knowing that Das is retiring, the officer glances through the former's cupboard to find one of his case diaries (titled "Kurup"). Krishnadas is mostly known as the officer who investigated the famous Charlie murder case long back when he was a DYSP, which paved way for a still-untraced fugitive named Sudhakara Kurup. As the officer reads through the diary, the story of Kurup unfolds on screen.
Born as Gopikrishna Kurup, Kurup is sent to the Indian Air Force forcibly by his uncle after he fails to acquire his degree. At the IAF, he meets and befriends Peter, who was also forcibly made to join the IAF despite his passion for music. Weeks later, Peter and Kurup along with some other inmates are sent to Bombay by the Air Force. There, Peter starts liking his new life while Kurup meets and befriends Sharadamma, who is the daughter of his family's old maid and falls in love with her. Later, Peter is informed that Kurup, who was hospitalized days ago, has committed suicide. He informs the same to Sharada. However, Sharada gets the message that Kurup is still alive and meets him in a subway, wherein Kurup announces the new name he currently lives under, Sudhakara Kurup. Kurup apparently created his death to escape the tedious life in the force. He soon marries Sharada and they leave for Persia (Pahlavi Iran at that time). However, further problems lead Kurup to leave to his hometown along with his office clerk Sabu.
In Kerala, Pillechan Bhasippilla who is Kurup's co-brother (Sharada's brother-in-law) and Ponnachan who is Kurup's personal driver in Allepey, welcome Kurup and Sabu. Kurup discusses a plan he made with the three other men - that he has applied for life insurance under his own name and an amount of Rs 8 Lakh can be obtained if Kurup's death was proved. Kurup decides to fake his own death.
The next day, an Ambassador car is found apparently involved in an accident and burnt badly next to a paddy field. A charred and killed person is found in the driver's seat. The police team headed by DYSP Krishnadas arrives and starts investigating. The car is identified to be that of Kurup. However, Das spots match, gloves and footsteps at the site, thereby confirming that it wasn't an accident but a murder. Das questions Pillechan which makes him suspicious of the latter. Das finds out burnt marks in Pillechan's body and takes him into custody. In custody, Pillechan admits that he had murdered Kurup.
However, Das finds that Pillai is lying. He asks his colleagues to cross-check recent man-missing cases that lead him to the house of Charlie, a film distribution company staff. Pillai is tortured in custody till he confesses that the four of them found the perfect victim in Charlie and subsequently murdered and burnt him along with Kurup's car, to fabricate Kurup's death.
Sabu and Ponnachan are also arrested. The missing Kurup is hiding at a lodge and a room boy informs the police about the same. However, the police is unable to trace him. Despite getting to know Kurup's exact route - Allepey to Ernakulam, then to his uncle at Mannar, further to his relative at Bhopal and finally to Sharada's aunt at Bombay - Das and his team miss Kurup each time. However, Das is ultimately able to find Isaac, Kurup's long-time friend with whom he was spotted by a peon, who informs the police. Isaac refuses to reveal Kurup's plan, but Das finds that Kurup is planning to migrate via a cruise ship. However, Kurup escapes on the cruise.
It is revealed that while in Bombay, Kurup was smuggling the force's arms which were pending post the war. He forms a smuggling setup with Isaac, then his close friend and Leo, a gangster. Kurup gets the need to evade capture and decides to fake his death for the first time. Kurup (then Gopikrishna) fakes his death and changes to Sudhakara Kurup with his family knowing about it. The false news is swiftly spread by Kurup's friend, a policeman.
Next, after marrying Sharada, both leaves for Persia where they lead a luxurious life. Kurup meets with Leo, who leads him to Prince Walid, son of the emperor. Walid is impressed by Kurup, and is assigned to smuggle crude oil without the knowledge of Walid's father. However, Kurup's greed resurfaces he decides to rob a high amount from Walid and then fakes his own death once again. The insurance was arranged only as a part of this big plan and Kurup with the help of his team in Kerala kills Charlie to fake Kurup's death. However, this time his plans go awry, thanks to an efficient Das.
Kurup was hiding right above the room when Das and his team arrived to arrest him at the lodge. He further hides at his aforementioned places in Bhopal and Bombay before planning to escape with the help of Leo. He even joins the police team disguised as a driver shortly before evading Das's eye and getting into the cruise, but Das is informed by Walid about Kurup's treachery. As the cruise leaves and Das find that Kurup is in it. Meanwhile, Kurup meets Leo and is assigned a new name 'Alexander' and a new passport. Once Kurup (now Alexander) walks out, he is called "Alexander" by Walid, who along with his bodyguards plans to kill Kurup. Das, confirming that Kurup will be killed, informs Charlie's family that he has avenged the person who is responsible for their condition. A few years later, Das gets conferred as an IPS officer and is promoted to the rank of Superintendent of Police.
At the end of the retirement ceremony, Das leaves the office, before which the officer who was reading his diary hands it to Das and salutes him respectfully. Das, leaving his official life behind and believing that Kurup is no more, leaves the office and the moment he leaves, a cop receives fax showing a lookout notice of an international criminal who is shown to be none other than Kurup. In the epilogue, it is shown that when Alexander was stopped by Walid, he just smiles to the camera and a newspaper story showing Walid's death in a car accident follows, indirectly suggesting that Alexander had set a plan B with Leo's help to end Walid in case he spotted him in the cruise. Various news stories and channel clips of the police searching all around the world for Alexander follow. Back to the present, in a busy street in Helsinki in 2005, Alexander is spotted and photographed by a person who works for the police. Upon realizing that he is being photographed, Alexander kills the photographer.
