As Ellen was running away from Espinoza she programmed her clothes to look like the brick wall that was behind her. Espinoza was able to see her because her hair was a different color then the brick wall.
It's not just a crack on the wall. "Find the cracks and exploit the discoveries to be revealed there . then move on to practice running headlong into the brick walls. Cracks crack first. Heads crack before brick walls. (from: STREET ART UTOPIA)"