Duplicate movie is about Sivankutty (Suraj Venjaramood) who is an unemployed person in Valiithode village. He ventured different business but all was failure and became pennyless. To earn his living he did all sorts of fraud activities. Sivan Kutty's friend was his uncle pint Sura . Nalini is Sivan Kutty's sister.
One day he borrowed Nalini's gold ornaments with the guarantee that it will be returned within a few days. To fulfill the promise he returned duplicate ornaments. This led to the imprisonment of Nalini's husband who without knowing the reality reached a shop to sell the duplicate ornaments.