I'm not very far into the Olympic Exclusion Zone in a run of Pacific Drive when the rain picks up. A T-shaped intersection looms just ahead, and as I make a right turn, the headlights play over the wreckage of a truck at the base of a hill, surrounded by trees. I bring the station wagon to a stop but leave it running and hop out, hustling over to the rusting hulk. Trucks are great finds, almost always full of junk I can use to upgrade my car or the garage that acts as my base of operations, and thus, always worth checking.

As I'm rifling through the menu that shows everything found within the truck, I hear it--some kind of high-pitched, siren-like sound coming from the woods behind me--and I freeze. My shoulders are tight and after a few seconds, I start to frantically check the area around me. Despite the hours I've spent driving around in the woods, the sound is like nothing I've ever heard in the Zone, or maybe anywhere. It has a distinctly mechanical, industrial tenor, something that sounds vaguely generated by a machine, but nothing about its oscillations or tone suggests what possible useful function a machine might undertake that'd generate such a noise. It feels...off. And it sounds like it's coming from just on the other side of the hill. Whatever is making that sound is somewhere in the woods, out of sight. But it is, distinctly, not far away.

I stand and listen, with rain falling all around me and only the headlights of the car illuminating the thin swathe of green between me and the road, for 10 or 15 seconds. The sound dies out and doesn't repeat. I wait, and wait, but at last...nothing happens.