The magician shows an envelope with a prediction and a deck of cards inside his box.
A spectator says a number between 1 and 52 and puts turns their hands palm-up so the magician can tilt the box and drop the cards onto the spectator's hands. The box is shown to be empty and none of the cards remain in the box.
To verify that all the cards are different, the spectator flips each card over, counting to the number chosen earlier. When that number is finally reached, the envelope is opened to reveal that the prediction matches the selected card!