Four teens dig up the time capsule that their parents buried in 1986 and never bothered to recover. In addition to the expected ephemera of mixtapes, Walkmans, photographs, letters, toys, and assorted junk, Elayah, Liam, Marcie, and Jorja discover something sinister: a hunting knife stained with blood and wrapped with a note. "I'm sorry. I didn't mean to kill anyone." The teens haven't just unearthed a time capsule: they've also dug up pain and secrets that someone-- maybe one of their own parents-- is willing to kill for.