I look at the dark sandpatch below me.

As I move forward it is suddenly basked in light. We must be at the first exit.
The light is flooding in through a gaping hole above.

I stare more closely at the shimmering grains of sand.
They go back to darkness. I am trying to detect movement in them, but there is nothing moving in here but us intruders.

I flip onto my back and swim onwards, watching the ceiling's rocky formations pass above me.