Have you ever heard a helicopter circling overhead? Even at a distance, the steady thunder of the blades incites a primal fear. It's a sound well known in war zones. Stand within yards of the landing zone, and you are overcome by the brute force of the machine as blasts of wind and overpowering noise fill the air.
Now, imagine not knowing what a "helicopter" is. You live peacefully in the high desert – a prey animal with acute senses. Then all at once, inexplicably, a relentless creature in the sky stalks, chases and pursues you as you stumble through the landscape in terror.