Stealth pulling a Batman, explaining how it’s done

Another call came from the vehicles. As Hall turned, I reached back, released the carabiner, and swung to the left. The trick to moving swiftly while climbing is using your arms and minimizing your legs. I slid around the corner and up.
Sergeant Hall was right-handed, which meant he favored his right side overall. I had chosen my “crouching” position on the wall beforehand, and it allowed me a quick exit to his left. When he turned back from the armored barricades, his eyes first passed through all the space I had occupied. When something vanishes from sight, human nature is to look side to side first, then up. Since his head was already moving left, he would turn his eyes back to the right, giving me a few seconds to complete my “disappearance” and add to the illusion.

Excerpt From Ex-Heroes, pg 169-170
Peter Clines
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