Adair's Added Surprise

They certainly won't be expecting THIS ending!

Let your spectator deal out some cards onto the table, into first one pile, and then into two piles.
In this way, the spectator can choose two cards in a "random" manner.
Let the spectator secretly look at the faces of the cards on the top of each pile.
He can also show the rest of the audience as well, but you do not look at the cards.
Let's say the chosen cards are the Eight of Spades and the Six of Spades, as seen in the demo video.
Instead, you announce that you have a special card in your pocket.
The card has two faces, with the value of a different card printed on each side.
In fact, the two sides of the card are your prediction and will match the two cards chosen by the spectator.
You take the card out of your pocket and show one side- it is the Three of Diamonds.
"Not one of my cards" says the spectator.
You try again and turn the card around to show the Four of Diamonds.
"Again, not one of my cards" says the spectator.
Even though there are only two sides of a card, you turn the card over again, and this time it shows the Ace of Diamonds.
"Still not either card! says the spectator.
You turn the card over AGAIN to show the Six of Diamonds.
"You are still wrong- not my cards!" exclaims the spectator.
Are you in trouble??
You place the card behind your back, then bring it out again to show the Five of Diamonds.
"Not my card" says the spectator.
Finally, you ask for one more chance.
You proclaim that you are going to show your prediction card that matches BOTH chosen cards.
You turn the card over one last time- and it is the 14 OF SPADES!
When added together, the Eight of Spades and the Six of Spades total the 14 of Spades!
You are successful!

This is a participation trick that can invole the whole audience.
Each time you reveal the face of the wrong card, there is more and more laughter!
And the audience have witnessed SIX different magical changes on the to sides of ONE card!

NOTE: The printed instructions mention bringing the special card out from an ordinary envelope.
The instructions say that an envelope is supplied.
NO ENVELOPE IS SUPPLIED, and you do not need one.
Simply bring out the special card from your pocket, as Peter shows in the demo video.