Effect: The spectator is asked to sign a card , then the card is placed back in the deck and the cards are shuffled.
The magician throws the cards at a bottle behind the spectators.
The signed card appears in the bottle.
Method: David Blaine showed the spectators a different trick before this one involving the same spectator signing a card of the same number and suit that is forced when showing the card in the bottle trick.
He then keeps the card and does another trick not involving cards when he slips the card to one of the camera men or lights crew.
The guy then puts the card in the bottle while David distracts the audience with the trick.
Then he goes on to perform the card in the bottle trick and the card is forced, signed and the trick is done.
He then throws the cards at the bottle and the card that was recently signed is held on to.
He then tells everyone to look at the bottle and the card is slipped in his pocket.