Underground 3

I could hear a faint sound under me, in the bottom of the gallery, like something moving itself from one place to another. I was terrified and my muscles were tense, I noticed that I was holding tightly the rungs of the ladder. Despite the fear I started down, as I had no more options. I got to the ground and suddenly I remembered I had my mobile phone in my pocket. I could feel the sound every moment closer to me. I I picked up the phone and quickly opened it and turned on the flashlight...What?...what? that can't be happening, this is a nightmare!!