Peeking changes by Tybbe master

"PEEKING CHANGES" A magic effect where the spectator chooses a card and signs it, then the card is lost in the deck,
Then we put the card in the middle of a bank note and we fold it,
the card is the wrong card!!
but one flick on the card suddenly changes the card into the spectator's signed card!
the banknote it is completely clean,
there is nothing suspicious at all...
LEARN NOW..!!