Light at the end of the tunnel

"Know what?" I ask, my shrill voice echoing off the cavern walls, but there's no answer. I stand alone in the cavern. The explosion of colour which had appeared to me only moments before is now gone. It's just me. "Over here!" A voice calls up ahead. Squinting through the dark, I see a flicker of light. I squeeze my eyes shut tight. Then open them again. I must have imagined it. But no, there it is again. With an irritated sigh, I walk towards the bright light. As I continue a bit further, I find dark craggy walls are closing in, creating a tunnel. I reach out to my sides with both hands touching the walls, as not to bump into them. I continue my trek, following the bright light at the end of the tunnel. Funny where have I heard that before? But I push that out of my head, too on edge to be cracking mental jokes. I'm real close now. The light's growing brighter. I blink, holding my hand in front of me to protect my eyes from the harsh light, only for to see the light flicker once more, and turn out.