This effect was created by Jack Hughes c. 1945 and is featured in his wonderful book World of Magic Vol. 2. Stevens Magic and Gimpy has recreated a perfect version with the permission of Derek Lever (the current owner of the Jack Hughes line).
The trick is great. Normally I would love to feature the video that Shawn Reida has done and is on the Stevens Magic website. Unfortunately, his performance misses the point of the trick and I believe ruins the overall effect. The big difference in the actual effect (and even the description on the Stevens website) is the four cards are chosen, they are all wrong, so the For Sale sign goes up. Then the magician asks what the actual card was, and now when the sign is lifted (without being turned around) the prediction has changed to one jumbo card. Having saved the day the magician now turns around the sign and hangs the new one: Offer Withdrawn. Which is more magical and funnier.
Shawn is a great and experienced performer so I’m sure this was just an omission under time pressure, but I wanted to mention it here. It is a really good effect otherwise 🙂
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