Nathan notices things other people walk past. Sasha never walks past anything at all. When a stolen afternoon in an off-limits corner of their high school turns up a folded, twenty-year-old note, the two of them expect nothing more than a strange little mystery to pass the time before graduation. They're wrong. The note points to a secret their school has spent a decade burying — a trusted teacher, a silenced student, and an institution that decided whose future mattered more. As Nathan and Sasha dig deeper, piecing together the truth in stolen moments at their hidden treehouse, they're pulled closer together even as the danger around them grows sharper. Because some people will do anything to keep a secret buried. And Nathan and Sasha are running out of time to decide how far they're willing to go — for the truth, and for each other. *The Note Left Behind* — a senior year they'll never forget, for all the wrong reasons.