I've been doing a simple trick where I force a card on someone and have them put the card back into the deck. I give the deck a shake and show the deck. There is now one card in the deck with a different color back...It is their card. Well, I did that today and forced the wrong card! Eep. Instead of stopping, I was able to use a double undercut when the card was put back into the deck and get the two cards (the one the person picked and the one with the different color back) to the bottom and then to the top...Once that happened, the red card was on top with their chosen chard under it. I double lifted to show their card with a red back (This was with a blue deck.) Not quite as impressive as the person could not nspect the ard, but I saved some face. "Double undercut" and "DL" are the double words of the day.