Originally Posted by crich70
I Have Lived in the Monster & Whoever Fights Monsters: My Twenty Years Tracking Serial Killers for the FBI both by Robert K. Ressler.
An excellent recommendation.
For unintentional comedy, I've always liked Ressler's story about choosing to be alone with Ed Kemper and what Kemper took that opportunity to say and do. It was a mistake the author never made again when interviewing any other incarcerated murderer.