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.
The material provided here is paper thin: After a tragic prologue lifted from the screenplay structures of "The Changeling" "Don't Look Now" and "Dead Calm", "The Descent" settles into it's main narrative of six young ladies who decide to reclaim a sense of youthful danger in their responsible adult lives by going on a caving expedition in the Appalachian mountains.
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.
I'd replace The Shining with Nicholas Roeg's Don't Look Now, however, in that there's a suggestion throughout that the ghost of Sarah's child is trying to warn her.