My Friend Dahmer (2017)

True crime told from the school hallway. Cartoonist John "Derf" Backderf knew Jeffrey Dahmer as a teenager and began his autobiographical comic about those years in 1994, after Dahmer was murdered in prison. Marc Myers's film keeps the book's unsettling angle: the killings lie in the future, and what you watch is a lonely, strange boy and the classmates who half noticed. Ross Lynch is genuinely disturbing as Dahmer, with Alex Wolff as Derf. Pick it if you want the psychology of a case without the gore that usually comes with it.