What would you do if you saw a man cut in half walking towards you? You'd probably freak out, just as most of the people in this video did after seeing comedian Andy Gross walking around with both arms around his legs. I don't know how he managed to create the body-cut-in-half illusion, but he does it incredibly well.
In fact, it's done up so good that the vast majority of people who encounter him almost always run in the opposite direction.
Skip to 00:25 if you want to see the most hilarious reaction of the lot. Enjoy!