David Copperfield's Chinese Wall Penetration

Experience David Copperfield's mind-bending illusion of penetrating a Chinese wall with just two matchboxes and one card. Show the audience two open matchboxes, where one contains a firmly attached colored dot. Place the boxes side by side with their lids facing outwards and insert the card between them. The audience can check which box the dot is in again. Close the boxes, and the dot has magically passed through the card to appear on the lid of the second box! A simple micro-magic trick you can perform immediately after reading the instructions.