I read the book The Alienist a while back, really gripping stuff if rather graphic but that's what makes a great story, when your imagination runs riot.
Netflix are now showing season one of The Alienist and it's a belter. Set in 1896 it's the story of Lazlo Kreizler and his hunt for a brutal serial killer. Kreizler is an Alienist, what nowadays is called a psychologist. The plot twists and turns and not wanting to give too much away the it is a very dark and sometimes harrowing watch, strong stomachs are recommended too.
https://youtu.be/YtzgFRBvRy8