Thankam follows the story of Muthu and Kannan, two gold agents from Thrissur, known as the gold capital of India. As they travel across Kerala and Tamil Nadu, delivering consignments of gold, their lives take a dark turn when a routine trip leads to unexpected complications.

The intense rivalry between two police officers—CI Jayashankar and SI Karthik takes a dark turn when a body is found in Jayashankar’s house, and he becomes the prime suspect in a murder investigation, which is led by Karthik, adding a layer of tension to their already strained relationship.

Ayyappan, a police officer, is an upright man who always strives to do the right thing. However, things change when a retired army havildar, Koshy, settles in his village and the two egos clash.

Harish Madhav a straightforward cop and Nishanth a college professor get entangled in a crime and one has to fight for his integrity and other has to fight for justice.