The three Locke siblings and their mother relocate into their ancestral home, Keyhouse, after their father is murdered under unexplained circumstances. They discover a cache of mystical keys that may be linked to their father's death. A sinister demon awakens as the Locke children investigate the many keys and their distinct powers, and will stop at nothing to steal them. Locke and Key is a coming-of-age mystery about love, loss, and the unbreakable relationships that define family, written by Carlton Cuse and Meredith Averill.