In the classic movie, The Princess Bride, we find our hero trying to save his love from the hands of the evil Vizzini. He challenges him to a battle of wits where Vizzini must discern which cup has poison and which is safe. Then, both will drink and the winner is the one not dead. The trick was on him, though. Both cups were poisoned. Wesley, aka Dread Pirate Roberts, had developed a tolerance for the poison, so regardless of which cup Vizzini chose, he would die and Wesley would live.