The Unabomber was a lone wolf terrorist who carried out fourteen bombings that left three people dead and another twenty-three injured. A cunning genius, he dodged his FBI pursuers for nearly two decades, terrifying Americans from coast to coast.

Agent Kathy Puckett, a spy hunter and highly trained psychologist, served as the turning point in the FBI's efforts to understand the mind of the faceless killer. Her insights helped send more than a hundred agents to a remote cabin in the mountains of western Montana on April 3, 1996.

There the FBI captured Theodore J. Kaczynski, engineer for the most notorious bombing spree in U.S. history.

This is the story of the FBI's investigation of the Unabomber and the agent who brought him to justice.