Street Magician Baffles People With Arm Through Window Trick

Rahat is a street magician with an unfortunate problem: he locked his keys in his car. He's had no luck getting the lock open with a coathanger, so once he's enlisted help from a passerby, he tries his only other option and puts his arm straight through the glass with magic. Witnesses absolutely freak out as he pushes his arm straight through the car window and pulls it right back out with no issue. How does he do it?