10 Disturbing Facts About Mindhunter's Serial Killers

The key interviewee, especially in series one, Ed Kemper is eerily calm as he recounts his murders to Tench and Holden. The 'Co-ed Killer' almost befriends Holden and opens up so much he becomes key to his studies.

In the world, however, Kemper doesn't seem to think much of his fellow serial killers. At one stage Kemper was in the same prison block as fellow monsters, Charles Manson and Herbert Mullin.

Mullin, in particular, didn't impress Kemper as he remarked how Mullin simply killed people for 'no good reason'. He described how he almost trained Mullin to do as he was told, in what he called 'behaviour modification treatment'.

It's somewhat bizarre to the everyday person that someone would compare themselves to another murderer and almost play down their 'achievements'. Then again, that's what makes such characters so difficult to understand and is ultimately what drew the FBI into delving deeper in the first place.