The door slams shut behind you, and there's almost a 'click' noise....could it have locked behind you?

It's darker here -- almost as dark as the first tunnel, and much damper. Lichens grow along the walls, with deep scratches in them that could have been made by human fingers. What could have made handprints that gnarled, though?

Up ahead, there's a sliver of light...could it be the way out?