Because they all have secrets they want to hide which were about to be revealed. Simon dies of a peanut allergy. Till where I've reached in the book, they are speculating that someone had put peanut oil in his water. Only thing is, Simon was hated by all for this group tat that he had created, where he exposed everyone's secrets about who they used to secretly hook up with, who was cheating on whom and who had cheated in Wins chest. He had so many sources
Yeah, as you said, it follows four high school students and who became suspects in the death of their classmate during the detention and it's a first in a series that includes a sequel and a spin off. And the book is told from the alternating perspectives of the four students, which are like Brown, Andy, Nate and Cooper. And each chapter reveals a new clues and twitch that keeps the reader guessing and to the end