This is one of the funniest, yet astonishing, yet mind driving gags you can do to someone. First have them chose a card from the deck or have them think a card or just anything in which you force a card on someone. Them pretend to continually guess incorrect cards as you urgently rush through the deck. Then you say.
"Hey, wait a minute, your card isn't even in here is it?"
Stow it away and they rack they're heads. Then in a low voice say...
"Is this your card!!!"
...And pull off your shirt to reveal an undershirt with they're card covering the front.


