Nattukku Oru Nallavan is the story of an honest police officer (Rajinikanth) and his fight against a dreaded criminal named Dddy (Anant Nag) who indulges in organ transplant mafia.

The CBI is in search of Sooriyan, an intelligent security officer of central ministry, who is accused of murdering a central Minister. But he has taken shelter in a remote village.

The story begins with Kunjidhapadam (Aravindan) who comes from a small place to the city for an interview and he manages to find place to stay with his distant relative Subramanyam who is actually a defaulter on loans taken on interest. He is absconding b