The Descent (2005)
How deep is it? This spelunking horror is set in an unmapped cave system in the Appalachian Mountains which means its impossible to know exactly how deep the caves run, but its pretty damn deep.
The explorers: Sarah (Shauna Macdonald) is one of a group of extreme sports-loving friends who decide their next adventure should be an underground one. Should've gone skydiving instead.
Whats down there? Apart from treacherous friends, the caves are home to a race of blind, carnivorous crawlers. Yikes.
Chances of getting out alive: Non-existent. Ignore the sequel. Never happened.
