The ZIG ZAG girl magic trick,,,does anybody know how it works?!

The ZIG ZAG girl magic trick,,,does anybody know how it works?

The trick hinges on two things: 1) People will not suspect the woman is actually responsible for the trick, and 2) The box is larger than it appears.

The black strips down the sides make the box appear more narrow. In reality, all that black space is empty and usable. The box accommodates the woman better than it appears to (though not by much - it's still a very tight fit).
The blades are inserted into the right side of the box. It looks like the blades take up more space because the handle is much wider than the blade; when inserted, the handle fills up the width of the box on the outside: but the blade inside only slices a portion of the box. To hide this, the blades are filmed going into the box from the side, not from the front or back.
The sliding contraption is not as narrow as it seems. Black paint hides a large column that gives space for the girl to squeeze into. The designer of the box must give the most space to the woman while making it appear as small as possible.
Unlike more conventional magic tricks, this illusion relies heavily on the skill of the woman inside, while the magician outside is just a demonstrator. The role reversal helps the illusion. Because most people assume the woman is just a helpless tool for the magician, few will suspect that she is actually in charge of this trick. The success of the illusion rests on the woman's ability to fit into the smallest possible space.