When eleven-year-old Max discovers that his sweet, cookie-baking grandma is actually a retired supervillain, life as he knows it gets turned upside down. With old enemies reappearing and hidden gadgets everywhere, Max must navigate a world of danger, adventure, and family secrets. Will Grandma stay retired, or will her past come crashing back? "Grandma's Secret" is a thrilling, heartwarming tale of family, heroism, and the surprising powers of grandparenthood.