Imagine having a spectator freely select any card (no force). The card is signed and replaced back into the deck. You state that by magic you will make their card rise to the top of the deck. You snap your fingers and turn over the top card, then you are waiting for your big applause when your spectator tells you that it's their card. This indifferent card is slid into a paper-thin clear black plastic sleeve just large enough to hold the card. While the sleeve is held between thumb and forefinger, and with no hand movement of any kind, the indifferent card slowly and visibly changes into the signed selection. The spectator can remove the card himself. There is nothing else in the sleeve!