Griffin Campbell and his family move to the old Tremont hotel in the town of Sulphur Springs. The entire town believes that the hotel is haunted by the ghost of a girl named Savannah, who disappeared over 30 years ago. When Griffin and his new best friend Harper try to solve the mystery of what happened to her, they find a portal that lets them travel back in time, where they learn that the secret to solving the mystery is meeting Griffin’s own father!