I climbed in, and crawled down the ventilation shaft. I started to hum a tune but it died on my lips. I began to feel an itch... and it went downhill from there. I had a strange feeling of deja vu as my body rushed with poison. I took my final breath as the death took the last of me...

...and I snapped back to reality. I was standing next to the vent, feeling very jittery and very much in need of rest. No chance of getting one down here, though.

You won't learn anything by crawling down the air vent and dying. There is a critical clue but it's not here. Well, kind of.