While some filmmakers aren’t satisfied unless they’re creating genres all their own – Darren Aronofsky, Richard Kelly, Wes Anderson, et al – others make their mark simply by injecting some new blood into existing ones.

British newcomer Neil Marshall fits into that second category, and though he’s got only a few films under his belt at this point, he’s already established himself as a genre director worth keeping an eye on. Marshall emerged on the scene in 2002 with the unique creature feature Dog Soldiers, a tense and visceral werewolf movie with a Predator-like setup; this week he returns with Doomsday, a post-apocalyptic combo of biological horror and over-the-top comic book-style action. Judging from the film’s trailer, Doomsday treads some very well-worn cinematic ground (it’s tough to watch the previews and not be reminded of 28 Days Later, The Road Warrior, Escape From New York, et cetera), but I have a feeling that in Marshall’s hands it won’t end up being a more-of-the-same kind of movie.

That’s especially true since Marshall’s last movie, also built upon a familiar-sounding premise and with a virtual unknown cast in the lead, ended up being one of the finest horror films of the new century.

I’m talking, of course, about The Descent, Marshall’s successful 2005 film (released the following year in the U.S.) about a group of female cave explorers being terrorized by some truly creepy subterranean beasties. The film wears its influences right on its blood-stained sleeves – essentially, it’s an underground version of Ridley Scott’s Alien – but is so exceptionally well-made that it feels like a true original anyway.

Opening with a horrific sequence that has nothing whatsoever to do with caving (but does, thankfully, have actual bearing on the plot later on), The Descent quickly falls into a compellingly tense groove, as an all-woman group of outdoor thrill-seekers get together for a self-guided caving expedition in the Appalachians. These ladies, refreshingly, aren’t your usual horror-flick airheads, but rather a nicely fleshed-out set of characters; the one we associate with first is Sarah (Shauna Macdonald), who’s recovering from the death of her husband and daughter and is still struggling to keep it together. The film’s first act creates an impressive amount of dread and sets up plenty of conflicts within the group to play out later on – I hate to sound so clinical, but having taken my share of screenwriting classes, it’s awfully nice to see a movie actually do some of the things it’s supposed to.

At any rate, things turn seriously scary soon after the ladies descend into the abyss, when a cave-in blocks the only exit from the dank, dark, deep-underground series of caverns they’ve unwisely chosen to spelunk in. After a few internal squabbles – and a terrifyingly claustrophobic crawling-through-a-tunnel sequence that makes me shiver just thinking about it – an even more immediate threat emerges: sightless, cannibalistic, frighteningly humanoid creatures who proceed to pick off and devour our heroines one-by-one.

Marshall delivers the jolts fast and furious as the film progresses, deftly combining the intense psychological terror of being trapped alone in the dark with the expected (but well-executed) creature-flick bloodletting. The monsters themselves are particularly effective, since Marshall creepily keeps them in the dark for most of the film, revealing them in all their gruesome glory only at the exact right moments.

The most surprising element of The Descent, however, is the film’s worthwhile attempt at psychological depth, an area in which it actually surpasses many of the films that inspired it. By giving us a hero who’s battling her inner demons as well as flesh-and-blood ones – and also setting up a juicy conflict between her and headstrong group leader Juno (Natalie Mendoza) – this movie resonates the way horror films way too seldom do, especially in the beautifully bleak ending of the film’s original British version (which you can catch on the unrated U.S. dvd).

Certainly not for the squeamish, claustrophobic, or weak of stomach – no, the gorehounds won’t be disappointed here, either – The Descent makes the most of its stripped-down setup and innovates not because it’s drastically different from a hundred other horror films you’ve seen, but because it’s clear that the filmmakers here simply tried harder to make it memorable. It bodes extremely well for Marshall’s future as a reliably entertaining genre director (could he be the next John Carpenter?) and sets the bar pretty high for filmmakers looking to follow the same path.