Ripperology is defined as being the study of the infamous serial killerJack the Ripper. Though the term has not made its way into the mainstream, those who study the case, or are simply enthusiasts are referred to as 'Ripperologists'.
This does not simply refer to finding out who the killer was, but who all of the victims were, along with various "evidence" such as the highly debated credibility of the Ripper letters.
"The study of the Jack the Ripper is called 'ripperology'."
"Who is Jack the Ripper, and why do I keep hearing his name? Why not ask a ripperologist?"