A serial killer terrorises the city of Kolkata and leaves behind verses of Bengali poetry. The police seek the help of a retired officer to unravel the case and find the perpetrator.

Based on the novel Magno Mainak by Sharadindu Bandyopadhyay, the film portrays the iconic Bengali detective Byomkesh Bakshi along with his friend Ajit Bandyopadhyay as he investigates the murder of a Pakistani spy named Heena Mallick. He begins the investigation at the request of a political leader, Mr. Santosh Samaddar, who was a close friend of Heena's parents and had given her shelter after her parents' death. Will Byomkesh succeed?

A child bride grows up to be an enigmatic woman presiding over her household, harboring a painful past as supernatural murders of men plague her village.

When upright cop Arjun Maitra takes on Kolkata's feared don Bagha and his henchmen, he must battle a broken system and navigate bloody gang wars.