A mysterious invitation. An island in the middle of nowhere. And a race for a mysterious inheritance that suddenly turns into a game of life and death. Just before Christmas, Marc is supposed to meet his grandfather, a wealthy tech mogul he has never seen before, on his private island. But when he arrives at the deserted isle, the eccentric old man has vanished. Instead, a deadly threat lurks among the palm trees and high-tech gadgets. A trail of strange clues leads Marc through a green hell, to treacherous hunters - and to a secret that will change everything. Only by solving all the puzzles will you escape the dark island and survive. 24 puzzles - 24 doors - and only one way out. The new Advent thriller for all adventurers, brainiacs, and escape room fans. This book will put your brain cells to the test. Because only if you manage to solve a riddle will you find out where the story goes next. For an exciting Advent season.