The magician puts two cards aside on the table saying that they are two predictions.

Now, the magician teaches that all the backs of the deck are different. 52 cards with different backs.

The magician passes letters and asks a spectator to stop him whenever he wants, and the moment the spectator stops him, he places one of the prediction cards face up among the rest.

Now he passes letters again, until the viewer stops him again, and
place the other card face up again among the others.

The magician qualifies that the spectator has said that he stopped when he wanted, and magically the letter that has been left face to face of the prediction, is exactly the same.

Interestingly, the second letter prediction has been face to face, exactly with another exactly the same.