Which one is....?

I've been meaning to update the blog with another fabulously witty and incisive post about my life, but I've been too lazy, un-witty and preoccupied with other stuff at the moment. So here's a pic a friend sent to me the other week. The photo is doing the email circuit I'm sure, but the more I study the faces of the guys in the photo the more hilarious it is, so I felt compelled to share (the joke is more striking if you click for the enlarged image and study the faces). Enjoy.


Which one is.....?