(07: 09) Liu has two cards in his hand, and writes his signature on one card and the counter-signature on the other card (at this time, the movement needs to be very smooth, so people can't notice that there are actually two cards, which is not difficult).

(07: 22) Show your cards in the mirror, and there are still two cards in your hand. The last one is the reverse signature.

(07: 3 1 sec) The key of the whole magic is that in this second, these three pictures show that Liu quickly opened the card with the middle finger of his right hand and hid it in his right hand. The whole action lasted less than a second. Admire!

(07: 32) At this time, the left hand only has a reverse seal card prepared in advance, and the right hand covers the front seal card.

(07: 34) At this time, the cameraman cooperated to move the lens to the desktop, and at the same time, Liu's right hand put the official seal card into his pocket (or other place) to hide it.

07: 52) will display the reverse signature card. The right hand has completed the action of hiding the original card with the cooperation of the cameraman.

08: 15 seconds) Magic completed. You can compare it with Liu's positive signature signed on the spot. The two signatures in the card are in different positions, the reverse side is in the middle and the front side is biased to one side.

Summary: this magic is still based on superb technology, without auxiliary props, pure close-up magic.