How did David Copperfield do the Great Wall Illusion?

Answer 1

When David Copperfield goes inside the first box there was a switch made, copperfield goes under the box and goes into the hollow stairs he then gets carried away inside the hollow stairs. A lookalike in shadow form pretends to walk through the first part of the wall, after he plays his part he gets inside the hollow base platform. By that time the assistance's pull the sheets away to show that he walked through the first part of the wall.

The stairs that copperfield is in is behind the camera boom as it makes a complete rotation over the wall. The assistants on the other side of the wall take the same stairs and put it next to the other plate form. The assistants climb the special stairs and hold up a small white sheet of cloth. It looks like David Copperfield is pushing his and and face through the cloth. The secret behind this action is that the person on the right is just controlling a pair of fake hands which he controls with his right-hand. The person on the left is just pushing a fake face through the cloth with his left-hand. The two assistants then drop the small sheet cloth and listen to the wall to see if David is all right. They then slowly roll down the sheets to cover the frame box up and make sure it is tucked in good, they go down the stairs to wait for copperfield to make his way through the second part of the wall. All he has to do now is get out of the hollow stairs and inside the box and watch his angles with the light. He then comes closer to the light so it looks like he is coming through the second part of the wall. He pulls the sheets away to reveal himself, the white cloth stays on the floor because it contains the props.