Stund trick Duffie

You shuffle a deck, place it on the table and invite a spectator to cut it. You bring out a packet of four cards and proceed to tell a story about going to a magic shop and wanting to buy a trick. A joker is turned over, then sent to the bottom. It rises to the top. You continue to place the Joker at the bottom, but it continues to rise to the top.

Eventually you say, it became apparent that all four cards could be Jokers! However, when you show the cards, they are all the same, but they are all blank! You definitely wanted to buy the trick, but you are too late, because now you instantly show all four previously blank cards have "SOLD" signs on them!!! Magically a "SOLD" sign vanishes from one of the cards. That is the card you bought! "Let's see if the magic acard works," you say, as you wave the card over the cut deck. The spectator turns over the card he cut to - say the Jack of Spades. BINGO! When you pass the MAGIC CARD through your han, the Jack of Spades appears printed on it! You hand it to the spectator who wil be STUND!