Synopsis: After a death of a minister leads to suspected murders of an activist, a doctor and a police officer, the family of the cop approaches the court for CBI to take over the investigation. Enter Sethurama Iyer and his team, but the investigation, which is later referred to as one of the toughest the agency had to face, takes them on a ride where they hit more dead ends than uncover new clues. Along with the probe, threats to the chief minister, non-cooperation stance from the police and personal agendas of several people who wanted the CBI to take over, further threaten to derail the case. How Sethurama Iyer, along with the help of his trusted aides – old and new – finally zero in on the ones behind the series of murders and reveal their motives form the plot.