Duo Flight by Leo Hartz

Effect:
A spectator counts ten cards from a red backed deck and they are sealed in a marked envelope. A second spectator counts ten cards from a blue backed deck. Two spectators each select one of these ten cards and after they are replaced with the other cards all ten cards are sealed in a second marked envelope. The two selected cards travel into the first envelope among the red cards, leaving only eight blue cards in the second envelope.

Special requirements:
Two decks of cards are needed; one pack having red backs, one pack having blue backs. It is also necessary to have ten extra cards with backs matching the blue pack. Four of these cards are of one value and four of another. In other words there are two sets of four identical cards. The other two extra blue backed cards must be different but it does not matter what they are. The magician must also have a packet of envelopes, one of which has had the flap cut off, and a pencil. The best envelopes to use are those with long flaps. I suggest using a pencil which has red lead at one end and blue lead at the other.

Preparation:
From the blue backed deck remove duplicates of the two indifferent extra cards mentioned above and any six other cards. These eight cards are all put in one envelope and the envelope without the flap is slipped under its flap. These two envelopes are held together as one envelope and placed at the bottom of the stack of envelopes. Also remove from the same deck the two cards to correspond to the extra forcing cards. These are placed face up between the two ordinary envelopes at the top of the stack. On top of the blue deck place the two sets of four identical cards, arranged alternately, and the two indifferent cards making the top and bottom card of the stack of ten. Put this blue back deck back into the case. The red deck remains unprepared.. If you have the pencil handy, you are ready to perform.

Performance:
With the stack of envelopes in the left hand, or nearby on a table, give the red backed deck to a spectator to remove from the case and shuffle. Have him count ten cards on your extended right hand. Have him repeat the count, one by one, so that there can be no mistake. Place these ten cards face up on top of the envelopes, and immediately over the two hidden red cards, while you pick up the pencil with which you mark his initials on the top envelope. As this envelope is to hold the red cards, you use the red end of the pencil. Now draw this top envelope out from between the ten red cards on top of it and the two blue cards beneath it, thereby adding the two blue cards to the ten red cards. This is done as if showing everyone the initialed envelope. Then cut the cards to bring the two blue cards to the center of the pack of "ten" cards and put them into the marked envelope. The envelope is then sealed.

Having put the stack of envelopes aside for the moment, pick up the blue backed cards and remove them from the case. This deck is then shuffled by the magician. Actually a false shuffle is used which will retain the top ten cards in position. A second spectator is given the cards and asked to count ten cards, naturally from the top of the deck, face down upon your right hand. Square the cards and without in any way calling attention to the act, give the audience a flash of the bottom card which is one of the two indifferent cards. Hand the cards back to the spectator and have the count repeated slowly, one by one, so that there can be no mistake in the count. Again give the audience a flash of the bottom card which will be the other ordinary card. The audience have now seen two of the cards, which is unspoken evidence that all ten are ordinary.

Fan these ten blue cards and have a spectator select a card. As he goes to remove one tell him to select two cards, one for his neighbor. Take care that the two cards are removed together, as this will insure, due to the arrangements of the cards, that he will select one each of the cards which have duplicates already sealed in the first envelope. After these cards are noted they are returned to the packet of cards. The pack of envelopes is, picked up, and in doing this the stack is reversed, bringing the loaded double envelope to the top. With the blue end of the pencil the initials of the second assistant are marked upon the flap of the top envelope. Of course, really this is the flap of the second envelope, which already is loaded with the eight blue cards. Now lift the flap and insert the ten blue cards into the top (flapless) envelope. By grasping the marked flap draw out the envelope to which it is attached and leave the flapless envelope on top of the stack. As this is done the hand and wrist are bent so that the envelopes are on edge and the envelope with the marked flap is lifted up away from the rest. The flapless envelope is towards the performer and the extra envelopes of the stack are towards the audience. Thus the two packets of blue cards are subtly and simply exchanged--the forcing packet of ten cards is exchanged for the packet of eight indifferent cards, and yet the cards were "put" into a marked envelope. The second spectator seals and retains his marked envelope.

Finale. The work is now done and it only remains to have the spectators name the two chosen cards, command them to pass from the one envelope to the other, and to have the envelopes opened to prove that this has been accomplished.

The details of showmanship are, after all, up to the individual magician. However as each point of trickery is completely covered I suggest that too much emphasis cannot be given to the marking of the envelopes, the fairness of the counting of the cards, nor, after the two cards have been chosen, to the fairness of the selection of the cards. I also suggest emphasizing the fact that the one envelope has been in the possession of the one assistant before the blue pack was touched, and that both packs were held by the assistants before you were informed as to which cards had been chosen.