Saw-gestions, se7en of them, that’ll make me scream next summer

Howdy, I am looking for books that are crime horror like Saw, Seven, the Batman. Not necessarily gratuitous but that has that grimey feel and wacky killer theme. And/or who-dun-it slashers akin to Scream, Heart Eyes, or I know what you did last summer. I am a very mid reader who in his late 20s [...]