Rob Brydon is the games master who takes 13 carefully selected players on board the X-bus and asks them one simple question - where the X are they? With blacked-out windows, all they have to do is try to deduce where in the world they are, because at the end of every episode, they must place an X on a map. The closest stay on the bus - the furthest away is eliminated from the competition. In the end, one walks away with a cash prize of £100,000. Each of the ten episodes sees Rob take the adventurers on another incredible leg of the journey - a fantastical trek that turns Europe into a board game, with twists and turns around every corner. Epic challenges offer clues to those smart enough to figure them out, but players - and viewers - beware, there are also some red herrings scattered around.