AGT Audition Trick
He first spreads a deck of cards on the table and asks Tyra to pick any card from the deck. Tyra picks the Queen of Spades. Shin Lim then asks her to mark the card by signing her name on it and then put it back in the deck. Shin first makes her card magically appear on the top of the deck, takes it, and rubs it on his chest under the shirt. When he shows the card again, the card is blank! But that is not all. Shin then displays his chest to reveal he has the Queen of Spades tattooed right where he rubbed the card!
He then goes on to amaze Tyra with many more amazing close-up magic. But let's first focus on the first part of the trick. First look at the performance, and then read the explanation below the video.
How did he do it?
The most fascinating part of this performance is that Shin Lim has the tattoo of exactly the same card that Tyra randomly picked from the deck. How is this possible? Obviously, he had to know in advance exactly which card she will pick, so he could get the tattoo made before the performance. But how could he possibly know which card Tyra will select?
The reason is that all the cards are the same! Every single card in that deck is the Queen of Spades. So it doesn't really matter which card Tyra picks, the result will always be the same. It may look like Tyra is freely selecting the card, but she actually has no influence on which card will be selected at all. Magicians call this forcing a card.
And how does he make the card blank by rubbing in on his chest? This is also quite a simple trick. There are actually two cards. Shin has a blank card in an inner pocket of his shirt, right by his chest. When he puts the card with Tyra's signature under his shirt, he quickly drops it into the pocket and takes the blank card out of the pocket. He does this while pretending to rub the card on his chest. Notice that for a moment the card completely disappears behind his shirt. That's when he exchanges the cards.