Descent, The (2006)
A Great Allegory.
The Descent does well in copying and adding its own style to raise itself above common horror schlok. The entire piece is a shocking allegory of loss, much like Alien was an allegory to rape. There are genuine frights, drama, mystery, and scares as a virtual cast of unknown actresses tackle the terrors of being out of one's element. At points the claustrophobic setting is more terrifying than what's going on, but once one catches on to what's happening one's mind goes to dark places.
This was a solid 4/4, though the director's cut with its alternate ending lowers everything from classic psychological terror to schloky commonality. Stick with the original!