The Vault - Stabbed in the Air | Juan Pablo - (Download)The spectator selects a card, signs it and places it back into the deck. You then state that you will balance the cards on top of a knife and you won't manipulate them. After throwing the cards up in the air, you instantly stab the signed card. Stabbed in the Air is easy to do, you can set it up in seconds and you just need a normal knife and a regular deck of playing cards. You can perform this effect both stand up or seated at a table.