A spectator is invited to get involved. The rest of the audience is shown a large prediction (approximately 10″ x 12″), the ace of diamonds, which is out into an open-front frame for safekeeping.
An oversized set of playing cards is introduced. What the participating spectator doesn’t see (but the others do, much to their amusement) is that the cards are all aces of diamonds — so the magician can’t miss!
The assisting spectator is invited to select a card, and to the surprise of everyone else, the chosen card turns out to be the queen of diamonds. The trick has gone wrong!!
Not to worry; the magician is able to solve the problem : As he extracts the prediction card from its holder, it visibly changes from the ace into a queen, ending the routine as a surprising success.