Who I Killed at Camp Last Summer takes a first-person approach to the slasher genre, entirely from the killer's perspective. It centers on a pair of horror-fanatic siblings, Ashley and Alex Byer, who attend a two-week summer camp with their school. The outlook of their adventure turns grim, however, when campers start dying in supposed accidents. The deaths are reminiscent of a previous camp, which got decimated by another killer some twenty years before. Soon many campers die, and no one is safe, as an old evil seems to have returned. This unique tale plays with the typical horror summer camp tropes and uses them in new and fun ways, while also touching on difficult human issues such as depression, identity, and the struggle of belonging, in a way no reader will ever forget.