Face it, everyone has at least one serial killer, (or murder case or whatever) that they have a keen interest in, and have read a lot into. (E.G. Charlie Manson, the OJ Simpson Trial etc.)
For me, it's John Wayne Gacy. I initially found the idea of a guy, who used to dress up as a clown for children's parties, as a murderer and child molester quite disturbing, but my curiosity was peaked so I did some research into case.
I couldn't believe it, but this guy was seen as a role-model by all his friends and neighbours, and he would regularly host barbeques and parties for the local families to attend.
Which serial killer, or what case, do you have an interest in, and why?