Hosted by Alex Trebek, this game show challenged both the knowledge and the nerves of the contestants. The two competitors, a returning champion and an upcoming challenger, would be locked in isolation booths and shown clues for an unknown person, place or thing. When one contestant gives a correct answer, he would then be given the choice of keeping the money, or daring his opponent to answer the question. If the opponent gave the correct answer, he would take all the prize money. If he were wrong, however, the first contestant would get double the prize money.