Performer shows a pack of cards in its case. He withdraws the deck and announces he will magically make a card leave the deck invisibly. He requests that five cards be drawn. These cards are placed face down on the table so no one can see them. Performer now picks them up and asks someone in the audience to write down their names as he calls them off. After the cards are listed, he puts them back in the deck. Someone now looks through the deck trying to find the five selections. Only four are found in the deck! The performer opens the case the cards came in... the missing card is found to have left the pack and gone back into the case.
Explanation: When performer withdrew pack from the case, all he did was to leave one card in it, secretly learning its suit and number. When performer reads the names of the five cards, he says the name of this card instead of one of the drawn cards.