They Both Die at the End is a young adult novel and LGBTQ+ tragic romance written by American author Adam Silvera and published on September 5, 2017, by HarperTeen.

[1] Shortly after midnight on September 5, 2017, Mateo receives a phone call from Death-Cast, a company that can predict the deaths of individuals, informing him that he is a Decker, someone with only twenty-four hours (or less) left to live.

The introverted Mateo decides to try to push himself to truly live and reluctantly downloads Last Friend, an app developed to help lonely Deckers find someone to spend their End Day with.

Rufus receives a call from Aimee telling him that Malcolm and Tagoe were arrested when they attempted to hold off the police to give him more time to escape.

As their friendship deepens, Mateo becomes bolder and Rufus begins to take color photos for his Instagram page, as opposed to his usual monochrome posts, to signify his End Day.

On his way to the park to spend his final hours, Rufus puts on his headphones to listen to the video he took of Mateo singing at the club and steps out into the road without looking.

Officer Andrade's story: his only chapter talks about his release of Malcolm and Tagoe from custody, his partner Graham's death, and his efforts to shut down the website that caused it.

"[4] Kirkus Reviews noted that the book was "another standout from Silvera who here grapples gracefully with heavy questions about death and the meaning of a life well-lived" before concluding that They Both Die at the End is "engrossing, contemplative and as heart-wrenching as the title promises".

[2] BuzzFeed noted that "Adam Silvera not only poignantly captures the raw emotion of facing your own mortality but also creates entirely relatable and authentic characters you'll want to follow on their journey.

"[11] American Review stated that "this book is an important contribution to young adult literature because of its humanizing portrayals of queer, adolescent characters of color.

"[8] They note this is especially important "given the repeatedly cited issues of hegemonic Whiteness and heteronormativity in young adult publishing, particularly in speculative fiction.

"[8] The audiobook, narrated by Michael Crouch, Robbie Daymond, and Bahni Turpin, received a favorable review from Booklist, who noted that the voice actors brought "the full range of this story’s anguish and joy to the listener.

[18][19][20][21] They Both Die at the End is in development by eOne with Bridgerton creator Chris Van Dusen attached to executive produce and write alongside author Silvera.

[33] The prequel novel The First to Die at the End gives an introduction to the Death-Cast system and introduces the reader to a set of new star-crossed lovers.