Mammootty in 'Pramaani' plays Viswanatha Panicker, the corrupt president of a grama panchayat. Panicker is a self-made man who has become immensely wealthy through corruption. He is called 'Pramani' because he has in his custody several documents; the Pramaanams as they call it.

Creepy happenings in an abandoned mansion are attributed to the ghost of an ancient courtesan, back for revenge.