The gunman isn’t so sure. He removes his camo—they’ve been out on this mission for almost 20 hours with no action—and heads down from their perch to get a closer look at the carnage. And soon enough, he’s hit. Down but not dead. His lookout comes down—the two have got some history, including a bond with a downed comrade from the past—and tries to help. And the bullets start flying again. The only shelter from the barrage are the crumbling remnants of a brick wall—hence the title. And it’s from behind that wall that much of the subsequent action takes place.