The elevator begins to descend rapidly, so rapidly in fact, that for a short while you become weightless. Fortunately it decelerates quite gradually, and when it stops you step out into a long, winding underground passage. The doors that close behind you are built of solid rock, and blend in with their surroundings so as to give the impression of a dead end. You decide to explore the maze of passages that unfold before you. Will you go straight ahead, or down a side passage to your left?