You will need: regular deck of playing cards, one duplicate card (duplicate to card you will force), one blank card (or Joker), plastic bag and paper clip

  1. Take the force card, insert it into the plastic bag and seal it
  2. Take your blank card (or Joker) and place it on the top of the force card outside the plastic bag (details in the video)
  3. Fold plastic bag so it looks like both cards are inside
  4. Secure this setup by paper clip

Step by step

  1. Show the card in plastic bag to spectator - it will appear that there is only one card inside
  2. Force the card on him. Use your favorite method
  3. Once spectator remembers the card, ask him to place it anywhere inside the deck and shuffle it
  4. Take the plastic bag, remove the paper clip and place it on the top of the deck, leaving our blank card / Joker on the top
  5. Now the trick is done - reveal that the card inside the sealed bag matches his selection