Invisible Deck (Red Bicycle)
Often referred to as the world's greatest card trick, the Invisible Deck is the perfect trick for people new to magic. It is simple to learn and incredibly powerful.
You ask the spectator to think of any card in the deck. Don't say it yet, just think it. You tell them to imagine that random card reversed - face down - in a face-up deck. They can change their mind and think of a different card. It is truly free thought.
You pull out a deck of cards from your back pocket, and you spread through it. One card is face down in the face-up deck. The card is shown to be the card that they previously thought of. Impossible. And very, very easy to learn.