Sixteen-year-old Mattie Gokey has a word for everything, and big dreams of being a writer but little hope of seeing them come true. With the fresh pain of her mother's death lingering over her and the only out from her impoverished life being marriage to the handsome but dull local rich boy, Maddie flees from her home. She takes a job at the Glenmore, where hotel guest Grace Brown entrusts her with the task of burning a secret bundle of letters. But when Grace's drowned body is fished from Big Moose Lake, Mattie discovers that the letters could reveal the grim truth behind a murder.