I worked on Escape From Planet Earth at the end of 2012 and I was brought in to develop the background environment of this particular one sheet. As you can see from the first image, the idea was much different with the aliens escaping from Area 51 out in the desert with casino-style buildings in the background. The Weinstein Co also wanted the faces of the security guards to be seen. I sketched out the background as well as the faces of the guards as you see below. I also put some atmosphere in between the guards because they were getting bunched together too much and it was lacking depth. They're running on hardened dirt at this point, so there has to be some environmental reaction to all of these things running around.