Devadevan, an underworld gangster decides to appear in front of Justice Varma Commission, who is holding a probe into the serial blasts that claimed innocent lives.

Devadevan's claim of divulging solid evidence of the hands of several top politicians and gangsters in the blasts and communal riots that followed made many of his rivals sleepless.

Past: Devan, a suspect under trial along with his trusted right arm Mustafa is bailed out by Khan Sahib, a smuggler on behalf of David Abraham, a Dubai-based crime boss.

Devan pledges to support Hari, a youth from erstwhile Namboothiri Brahmin feudal family, who is in deep financial crisis.

David Abraham, who was now losing turf to Devan too joins them and provides explosives and ammunition required to create a severe blast along with a communal riot that could deviate public attention from the series of corruption allegations against his men in power, including Baba Rahim.

Mahathma was declared as an average venture at the box office compared to past blockbuster hits of Suresh Gopi-Shaji Kailas.