A blue deck of cards is displayed. The pack is turned face up and a spectator is asked totouch one card. That card is shown to be the only one with a YELLOW back. The selected card is returned to the deck and now all the cards appear to be yellow. Once again you remove the selected card and the remaining cards change back to blue. You then ask what happens when blue and yellow are mixed. Tne selected card is placed back in the deck and now all the cardsare green! Uses Hoyle brand playing cards.