This effect was invented by Joe Berg c. 1952. It was originally marketed under the name Atomic Mystery Deck in bridge size Aviator playing cards.
I applied a few of the changes suggested by Russell Lewis and it really makes the handling very clean. This comes in standard Bicycle poker sized cards and if ever you wanted to switch in a deck of cards during your routine this would be the one to do it for.
Effect: The performer removes a deck of cards from the case and holding same squared in his left hand, he allows one or two spectators to merely “peek” at any card, the two cards are looked at by lifting the corner of the held deck.
Performer proceeds to locate or disclose the two peeked-at cards. Spreading the cards in front of each spectator, they are requested to look through the spread face up deck and remove the cards chosen. To the spectator’s surprise the two chosen cards are missing!
Performer reaches into his trousers pocket and removes the two named cards! The two cards are placed face up on the table and one spectator is asked to place his finger on one of the cards. Performer places the selected card on top of the face up deck. Suddenly he ribbon-spreads the deck in a row and all the cards have changed to the same card as the selected card on top of the spread!
Now for the second surprise. Lifting the remaining card from the table he likewise places it on the top of the face-up deck and again with a spread all the cards have changed to the same card as the spectator’s second peeked-at card!
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