The denouement is pretty clear when survivor Sarah bubbles, head first, out of a pool of glop in much the same way a possessed Martin Sheen bobbed to the river surface before slaying Brando in "Apocalypse Now."
The final sections of The Descent which manage to evoke Ridley Scott's Alien (1979), Brian De Palma's Carrie (1976), Francis Ford Coppola's Apocalypse Now (1979) and even Rob Zombie's House of 1000 Corpses (2003) are bloody, brutal and tense.
This is also when the filmic allusions start piling up into their own sort of zombie brigade: scare quotes, if you like, from Don't Look Now, Carrie, Apocalypse Now, The Blair Witch Project, the Gollum sequences in The Lord of the Rings, The Texas Chainsaw Massacre, the original Alien, and in one sudden flash-reveal of a whole brigade of crouching monsters, a direct lift from Aliens.
They include explicit allusions (in addition to the movies already mentioned above) to " Picnic at Hanging Rock ," " Carrie ," “ 2001: A Space Odyssey ,” " The Third Man ," "The Fourth Man," " Don't Look Now ," " The Blair Witch Project " " Vertigo ," " Apocalypse Now "... and plenty more.
Marshall is also an astute 'borrower' of other films, from the piton clipping suspense of "Cliffhanger," to the video camera revelations of "The Blair Witch Project" to a combined "Carrie"/"Apocalypse Now" moment that wows with its audacity.
Along with some rather pleasing homages to classic movies (including, as far as this reviewer could spot, Apocalypse Now and Carrie) The Descent boasts fantastic action scenes, nail biting horror, impressive acting and a couple of darkly comic moments that ever-so-slightly ease the almost unbearable tension.