From New York Times bestselling author Adam Silvera comes an explosive examination of grief, mental illness, and the devastating consequences of refusing to let go of the past.

When Griffin's first love and ex-boyfriend, Theo, dies in a drowning accident, his universe implodes. Even though Theo had moved to California for college, Griffin never doubted Theo would come back to him when the time was right. But now, the future he's been imagining for himself has gone far off course.

To make things worse, the only person who truly understands his heartache is Theo's new boyfriend, Jackson. But no matter how much they open up to each other, Griffin's downward spiral continues. He's losing himself in his obsessive compulsions and destructive choices, and the secrets he's been keeping are tearing him apart.

If Griffin is ever to rebuild his future, he must first confront his history, every last heartbreaking piece in the puzzle of his life.