A Classic Packet Trick by Nick Trost now available in Bicycle cards!
The magician displays a four-of-a-kind face up (let's say the queens for example.) One at a time, each queen (clubs, spades, diamonds, hearts) magically turns face-down and then face-up again.
The audience is asked if they remember the colour of the backs of the queens (which they were blue) but the magician somehow causes all of the card backs to change to red! Immediately all of the faces also change to red, all the queens becoming red queens! For the kicker, the magician causes the backs of the cards to change yet again, leaving the spectator's totally bamboozled!
Easy to do, this classic Nick Trost trick should be in the arsenal of every magician.