Ask someone to name any card. Then you call Mr. Wizard on the phone, and he tells the person their thought-of card! How?
You’ll need a phone for this trick—cell or land line is fine. And an assistant you can phone.
Tell your assistant that when he answers the phone, you’ll say, “Hello, is Mr. Wizard in?” This cues him to start the trick.
He starts counting out loud, ‘Ace… 2… 3… 4…’ When he gets to the number of the card, you interrupt, saying to the audience, “He says he knew I was going to call!” Now he knows the number of the card, having been interrupted there.
Mr. Wizard then starts naming suits ‘Hearts… clubs… diamonds… spades.’ When he gets to the correct suit, you break in, “We have someone who would like to know their card.”
Mr. Wizard then confirms ‘4 of hearts’ (or whatever the card is). You hand the phone to the spectator. If others are watching, put it on speaker phone at this point. Mr. Wizard reveals the card! It seems to the spectator like all you did was get him on the phone!