I dont know if youve read John Douglas's books at all ?
FBI Behavioral Science (formerly know as )profile's first hand the old stories of who was the who with serial killers..
All the typicals and best known are mentioned in Mindhunter..Gacy,Bundy,Rader,and a lot more..
He profiled a lot of them ..
Mindhunter was a good book ,The Cases That Haunt Us and BTK were all great to read.
BTK shows you the sick and twisted world,in which Denis Rader built himself.He was a unit !
I reckon the author kept it interesting by mixing the stories up a bit ,throwing similarities between cases ,toing and frowing in many of his books.
Youll like em..Do It