在位于阿帕拉契山脉的乡间小镇地底下，有座已燃烧数十年的废弃煤矿。一支研究小队前往该地试图找出当年矿坑起火燃烧的原因，却意外挖掘出更令人吃惊的恐怖秘密……

Two miles into the earth, nine Appalachian miners struggle to survive after a methane explosion leaves them with one hour of oxygen to go.