I assume fantasy is also out based on the no sci-fi and no Stephen King request. That eliminates the majority of what I read.

How do you feel about true crime? In Cold Blood is a classic and a very engaging read. I'll Be Gone in the Dark is quite good and the killer had not been identified when the book was written. The Poisoner's Handbook gets into the origins of forensic science. The Blood of Emmett Till successfully presents Emmett Till is a human being while still framing his murder as the significant cultural event that it became. This last one is a bit controversial but If I Did It is very well written and very strange to read. The ghost writer's commentary adds to the book in very meaningful ways.