Cleanse

He shuffled down the hallway, pushing his broom and bucket before him. The building thrummed around him, shuddering with hidden energy. The laminate floor and the acoustic tiles seemed to fade as each ripple of force passed through them, revealing dark stone like smoke. Through the ebony surface, one could see thin black legs and wriggling bodies, scrabbling at the surface as though digging to escape, to burst from the black rock into the world of light. The janitor whistled a jaunty tune and stopped to mop another section. Behind him, the shadows flailed at their prison with silent fury.