A crew of coal miners becomes trapped 600 feet below ground after a disastrous collapse. As the air grows more toxic and time runs out, they slowly descend into madness and begin to turn on one another. Inspired by true events.
There are a few times when characters hyperventilate or panic. The threat of running out of oxygen is a constant fear and commands the narrative of the second and third act.
Some characters mention having children before they die. The children are never on screen and do not witness the deaths. Another parent dies in front of their adult daughter.
No one is eaten in the movie about the mining accident. Other comments answering yes are referring to a different movie by the same name about a killer fish.
One instance of a character vomiting. It's after the cave in, after they discover the remains of another character. A man turns away and vomits on screen. It's brief.
The entire film is about being trapped in mining tunnels. At some points characters get stuck in narrow spaces or have to crawl around a space on their hands and knees.