After a tragic accident, six friends reunite for a caving expedition. Their adventure soon goes horribly wrong when a collapse traps them deep underground and they find themselves pursued by bloodthirsty creatures. As their friendships deteriorate, they find themselves in a desperate struggle to survive the creatures and each other.
At 1:02-1:03 a character is looking around through a night-vision camera and you see a glimpse of what looks like a dead wolf. It doesn't die during the movie and it's in a pile of other bones of animals and people.
i don't think anybody actually dies that way, but there are a few scenes where woman are propelling from the ceiling with climbing gear, dangling, close to death.
AVOID THIS MOVIE if you're claustrophobic. seriously. much of the movie is spent within the cave and cave tunnels. characters can be seen army crawling through small spaces, getting stuck, etc.
a lot of it. steer clear of this if you don't like that. there's even a pool of blood or water or .. i'm not even sure, that a character is submerged into.
i wouldn't say tortured on purpose, but there's a scene where a broken bone has to be very painfully reset. also the monsters are sadistic in the way they attack and/or "play with their food".