The Descent is a 2005 British horror film

Ronan was no stranger to the dark, he couldn't say he liked it, but he was familiar with it and the dangers that lurked within. He'd already come to a conclusion of his own, one he was staunchly tight-lipped about, but found himself checking dark crevices all the same. Just in case. This one was unlike the others, unnatural in a way that was unfamiliar to him, all stone and no metal.

Something, or someone had died down there, he could smell it. Not a fresh stench that made his nose wrinkle in distaste, but something old, long dead, desiccated by the passage of time. Probably had been gnawed on by the rats, he couldn't see them but he heard them easily enough, how they skittered out of view, reacting a moment before he even moved.

The stone felt worn under his paws, almost marble smooth and good thing too as he couldn't see shit. It'd be easy to trip and get turned about in this place, he wouldn't have been surprised if the corpse was someone who'd gotten turned about, couldn't find their way and just died. Either from lack of water or starvation.