For me, it is the Ballad of Songbirds and Snakes by Suzanne Collins. It is so well thought out and the pieces slowly come together as you read, with lots of twists and turns in the story. Other contenders for me were The Secret Commonwealth by Phillip Pullman, Outcast by Michelle Paver and Russian Roulette by Anthony Horowitz. What is yours? I’d love to hear them.
Hyperion by Dan Simmons
I still think about Sol’s backstory specifically. honestly, one of my favorite chunks of writing I’ve ever experienced.