One day Mary notices a young woman sitting in her bookshop. As the afternoon passes, the woman remains, pretending to read a book and clearly waiting for someone who never arrives. When Mary approaches her, she tearfully confesses that she doesn't remember anything before that day. The only clue she has to her identity is a note she found in her pocket when she woke up on the beach, which says, "Katie, arrive at Mary's bookshop at 1:12." Mary takes Katie under her wing, and together they scour Ivy Bay for clues to discover who Katie really is. But after learning about a recent mugging in town as well as a man who seems to be following Katie, Mary thinks the more important question might be what - or who - caused Katie to loser her memory in the first place?