A thrilling new adventure in the best-selling series - filled with puzzles, riddles, secrets, and surprises! Prepare to test your wits and wisdom in the world's most exclusive puzzle competition - the Planhart Challenge - founded in 1973 by Sir Eriick Planhart! From the moment you open the box, you'll be partnered with other expert puzzlers around the globe, each one as dedicated to reaching the finish line as you are! Your very first choice will set you on a unique path, and there’s no going back. Are you ready to step up to the challenge? Box TWO isn't just bigger; it’s deeper, smarter, and packed with twists only someone like Sir Eriick Planhart—one of the world's most acclaimed pioneers in mathematics and physics—could dream up.