Beneath the Iron Grate

I pushed past the hall door and descended the concrete stairs to the ground floor. The outer air had no ceiling. It was cold and wide. Outside the glass entrance, set into the stone pavement, lay a thick cast-iron grate. Its surface was cold, pitted with dark rust. I crouched low, hooking two fingers into the heavy iron slot, and peered into the dark gap below. Water trickled faintly through the subterranean gloom. A low rumble stirred in my chest. This territory goes deeper than the surface.