Forced to choose between abortion or adoption, Olivia Carson's younger sister, Lily, runs away from home. Sixteen and pregnant, she never returns. But she writes. Once a year, Lily mails a picture of her son, Josh, to Olivia until his thirteenth year. Then it's Josh himself who arrives at Olivia's house, alone, terrified, and in possession of a notarized declaration from Lily. It begins, "In the event I go missing..." Josh has difficulty talking. He can't read or write, but he's a prolific artist, exhibiting skill beyond his age. His drawings are as detailed as they are horrific. Olivia soon realizes Josh's artwork tells a story. There's more to his arrival and to Lily's untimely disappearance than it seems. Using the drawings as a road map, Olivia traces Josh's path back to his mom. Each drawing sheds light on Lily's past and reveals a darkness that forces Olivia to question everything she thought she knew about her family.