An invisible black crystal ball is imagined. A spectator selects a card and signs the face. The invisible ball is pushed into the deck. When the cards are spread, a black spot is found on the back of one card. The card is turned face-up, revealing the spectator's signature. The signed card is placed over the spectator's opened hands. Magically, a black ball falls from the card into the spectator's waiting hands. Upon closer examination, the back of the spectator's card reveals that the black spot has vanished.