In Dead Letters, Caite Dolan-Leach tells the story of Ava, who is forced to fly home from her new life in Paris to her parents' failing vineyard in upstate New York when she learns of the death of her twin sister, Zelda. However, given Zelda's penchant for tricks, Ava can't help but suspect Zelda is still alive — especially once she starts to receive a cryptic trail of clues.