His name was H. H. Holmes and he is also thought to be THE Jack the Ripper because he was in London at the exact same time and was a medical professional. He went to medical school to learn how to kill people. He is fucking scary.
And Supernatural did an episode on him. I first saw it when I was like 10 and it still creeps me out to this day.
I read a book about him. He had multiple wives at the same time, almost all of whom he killed after separating them from and or killing their children. He was said to be incredibly charming and charismatic, and killed almost all the women he seduced.
Fun Fact: His documentary is on Netflix.
Multiple people involved in convicting H.H and sentencing him to death died bizzare deaths shortly afterward including members of the jury, the doctor who pronounced him dead, and even a priest that visited him before he died.
There is now a post office where the murder castle used to stand (it was burned down after Holmes was executed, thought they never determined the cause of the fire) and it is extremely haunted. Other people have claimed seeing him in the Museum of Science and Industry because it’s one of the only building in Chicago left from that time.
The Museum of Science and Industry is in one of the buildings originally built for the 1893 Chicago World’s Fair. H.H. Holmes exploited the large numbers of young single women coming to town for the fair and preyed upon them. His killing spree largely coincided with the fair, which was a hugely influential event in urban planning and modern trends of architecture.
There is a fantastic book about this, “Devil in the White City” by Erik Larsen. It’s about both the 1893 Chicago World’s Fair and about H.H. Holmes, two interconnected events. I originally read the book because I was so relieved that someone had finally written about Holmes (who’s strangely unknown in general knowledge) but I wound up fascinated by all the World’s Fair stuff.