Mickael Chatelain is a genius to not only imagine it, but to create a beautiful hand-crafted method to go with it.
Imagine holding up a playing card. One side facing you the other side facing your audience. The spectators see the card has a circle cut out of it. You explain to them that the hole is not round it is a square. The spectators look at you like you are crazy but sure enough when you turn the card there is indeed a square cut out of the card. You can repeat this as many times as your spectators desire.
Includes a gimmick card and online video instructions.