The trick is called as such because it requires you to have two mirror copies of the King of Diamonds and the King of Clubs. Nonetheless, it’s also possible for you to do this trick with any card as long as you have two of it. This trick also requires the use of a separate tool to make it successful. You are required to get a double-stick or double-sided tape. It should be invisible once you stick it on the back of the cards. Also see more tricks with cards here.
1. Before you start the trick, single out 6 random cards along with 2 cards that have the double-stick tapes. Divide these into two; each pile should be composed of 3 cards with 1 card with a double-stick tape on top. Grab the rest of deck then place 1 King of Diamonds on the bottom. Place 1 King of Clubs on top, then place the other two King of Diamonds and King of Clubs on top as well.
2. Once everything is in this setup, you may now begin the trick. Begin by setting apart the King of Diamonds and King of Clubs that you placed on top of the deck. Afterwards (with the other King of Clubs on top and the King of Diamonds at the bottom), starting from the top, begin placing one card on top of another from the deck, then ask the audience when you’ll stop.
3. Once they do, place the King of Diamonds on top (face-up) of the last card that you dealt. Place the rest of the deck (with the other King of Diamonds at the bottom) on top of the other King of Diamonds. With the other King of Clubs at the bottom of the deck, begin dealing out the cards one by one again, then, similarly, ask your audience when to stop. Place the King of Clubs (again, face-up) on the last dealt card then put the rest of the deck (with the other King of Clubs at the bottom).
4. Go through the deck, then pick the King of Clubs that’s face-up as well as the one that is directly above it (it should be its mirror). Do this for the King of Diamonds as well. Place the King of Clubs on top of the pile of the first card with the double-sided tape; this applies for the King of Diamonds as well. Make sure that the 2 cards stick to the ones with tape. You may now start chanting magic words for effect before magically revealing that the King of Diamonds and King of Clubs (the doubles) are actually not found in the two small piles but in the ones that you took from the deck.