I gave it a spin as well. I really enjoyed the level design, especially the forlorn abandoned factory-part. Would love to see more of that in a game. Maybe with more dimmed and spooky lights, and a slightly scary fellow sneaking about... >:D
Your modeling is great imo, the cave and factory are really nice and feel very genuine. The mountainous area not so much, but that's probably because of the backdrop more than the buildings there, which are also very nice!
As for the story I had an idea of what it could be, but I actually don't know if I'm right.
Edit: I just had to add this. A friend pointed this out to me, I didn't realize it at first. The narrator sounds SO MUCH like Trey Parker from South Park! Like holy shit similar :D If this happened by accident or not doesn't matter, it makes it better! I do love me some South Park!