Max and Isobel are gamers who love a challenge. So when Grandma Gert leaves behind a mystery to solve, they're both ready for the adventure. They'll need to stretch their memories, puzzle out clues, and think creatively if they want to unravel Grandma's final riddle. Can Max and Isobel figure out what Grandma's end game is - before time runs out? If you like or mysteries, check out what Max and Isobel are up against in !