An Ultra-Simple Approach to the packet Brainwave Effect

No, this isn't a book. It's a card trick.
But what a card trick! One of the best-selling, most popular card tricks of the past decade!
B'Wave has baffled princesses and presidents, and is used by professionals throughout the world.

Four cards supply three stunning punches! Someone decides on any queen. The four cards are cleanly spread on the table - the only face-up card is the chosen queen! Then you turn it over - its back is a different color from the other cards!
As final proof that you knew positively which queen would be named, you turn over the other three cards - they are all blank!

No sleights, no rough & smooth, no extra cards, just pure mind-boggling magic!