Both of The Descent films, if you care to know it, were loosely based on a rather interesting book of the same name that follows the the discovery and exploration of a vast labyrinth of tunnels and passages stretching throughout the entire sub-surface of the planet. This subterranean world is inhabited by the degenerate and brutal “hadals”, a group of humanoids so nasty that our interactions with them over the millenia are posited to have formed our historic belief in demons. And so we go to war with them. I say that the films are loosely linked though, because whilst Part 1, directed by Neil Marshall did exhibit some elements of the novel, Descent Part II is frankly just a crude attempt to further exploit the successes of the first film.
Basically, The Descent Part II begins as the Descent Part I leaves off, with the survivor Sarah making it to the surface whilst the search teams are ramping up their efforts to find the six women who’ve now been missing for a couple of days. All well and good. But then follows a search-and-rescue mission of such monumental incompetence and unpreparedness, complete with bumbling deputies, ill-equipped spelunkers, and even the catatonic Sarah dragged back into the cave system – it’s all just so unlikely, it really loses you almost before it begins. So yes, there are some suitably horrible claustrophobic moments and it’s not without tension or gross body-fluidy-bits, but generally the accents are weak, the remote Appalachians are replaced by suburban Surrey, and the murderously intelligent hadals are now just mindless flesh-eating zombies – its such a terrible waste of a really great idea.