Ten-year-old Gracie Rodriguez has made up many tales of fantasy for playacting with her grandfather on their routine outings together. Strangely, for the first time, she commits one to writing. It was at a "mystical urge," she says, and tells him, "It's along the line of apocalyptic for some reason." During their hike on the day the tale is finalized, she acquires various superpowers and unimaginable experiences ensue-evil character, seeking to steal her powers; alternate realms; and supernatural creatures. Gracie learns that a mystical creature has provided a mysterious superpower to assist her with mounting horrors. But will she be able to solve a riddle required to access it-in the apparent last minutes of her and her grandfather's lives?