An effect by Paul Gordon performed by Aldo Colombini. You show some Jokers. The backs of the cards are red. One Joker with a big X on its back is placed among the cards and now all the cards have a big X on their backs. One card with a big O on its back is placed among the cards and now all the cards have big O’s on their backs. Finally, the cards are all back to normal. The big surprise comes when five cards are turned over and a letter appears on each card spelling the word MAGIC (or any other message, a Royal Flush, etc).
You will need five blank-faced cards.