When the Light Went Out by Bridget Morrissey

Five years after the accidental shooting of Marley Bricket, her friends, who were there the day she died, reunite when a box of letters from Marley is found in her former home. The discovery leads them on a scavenger hunt that reopens old memories, wounds, and betrayals, and leads them to question what they thought they knew about Marley’s death.