Kambilikkandam Jose (Subair), a drug baron reaches down to Kochi to meet Pattakkalil Purushothaman Pilla (Vijayaraghavan (actor)), demanding a huge hike in his commission. Popularly known as Appichai, Purushothaman Pillai is one of the largest drug dealer in south India, along with Sethumadhavan (Saikumar (Malayalam actor)), his Fosterage son. Appichai calls back Sethu, who is on a vacation in a cruise ship in Goa. Sethu, on his arrival back in Kochi kills Jose, with the help of Balagopal (Ramu), the IG of Police. But the death of Jose creates a strong protest inside the state and the Chief Minister (Janardhanan (actor)) orders a detailed investigation on the matter. Narendran (Mammootty), the Assistant Commissioner of police, is assigned the charge of investigation. Popularly known as Nari (tiger), for his aggressive and belligerent style of behavior, Narendran, begins his probe by questioning Dr. Ratnakumari (Urmila Unni), the assistant surgeon, who conducted the postmortem of Jose. Nari finds out marks of physical assault on his face, which was not mentioned in the report. He reaches our to the family of Jose, who, on the next day is found dead in the suburbs of the city. Sethumadhavan, who also holds an illegal business partnership with the son of the state chief minister, is one of the most influential businessman in the country. Under the pretext of Karunyadeepam, a spiritual ashram, under Rema Bai/Rema Behan (Prabha Dutt), Sethu runs a vast drug network along South India. Narendran, through his strong and sharp methods reaches out to Rema Behan, who on the next day is found dead in her sleep. On his path, Narendran finds several obstacles including the son of the CM and several senior police officers and in the end, the CM itself, who decides to withdraw Narendram from the charge of investigation. At the end of the Talk with the CM Nari tells him that Sethu came here yesterday and showed a video clip about CM'S Son. CM lets Nari carry on with the investigat