Melissa Moore, daughter of Keith Jesperson, otherwise known as the Happy Face Killer, talks to A&E True Crime about what it was like as a child to learn her dad was a serial killer.

Investigative journalist and crime writer M. William Phelps talks about his 'friendship' with serial killer Keith 'Happy Face' Jesperson.

Killers who leave notes at crime scenes or mail missives to police and the press take a big risk. Read stories and watch videos about eight murderers who just had to put it in writing.