The Descent Part 2 (2009)

Immediately pissing away the stark, nihilistic brilliance of the ending of The Descent, this continuation of the story - rather than a sequel per se - has Sarah (Shauna Macdonald) somehow escaping the underground cave system, but stricken with that wonderful Hollywood plot contrivance of "amnesia".

Bizarrely then, while still traumatised and barely able to communicate, she is made to return to the caves by cinema's most moronic sheriff.

Sheriff Vaines (Gavan O'Herlihy) makes Rosco P Coltrane and JW Pepper look like the epitome of law enforcement excellence in comparison.

Every word that comes out of his mouth and every decision he makes - particularly when the expedition is back underground - has you praying for a carnivorous cave crawler to leap out of the darkness and rip his head off.

There are moments that come close to the greatness of the first movie but as this part isn't directed by Neil Marshall's expert hand (he's simply executive producer) much of it feels very artificial.

The story is also riddled with inconsistencies that make you question how much care was taken in the movie's production: - for example, the rescue party is supposedly retracing Sarah's steps into an abandoned mine that links into the cave system, but nobody realises it's all blocked by cobwebs and boarded up, so there's no way she could have come that way less than 24 hours earlier; then the cave mouth off of the crawlers' feeding ground is large enough to drag a dead moose through one moment, then suddenly there's barely enough room for a woman to crawl out to freedom.

Certainly more an adventure story than a straight-up horror, as the original was, The Descent Part 2 is an unnecessary 'sequel' to a classic, but is okay as an hour-and-a-half of subterranean thrills and spills to pass the time on a wet and windy afternoon.

The Descent (2005)

Neil Marshall is one of the UK's finest directors, with Dog Soldiers, Centurion and Doomsday to his credit, but the action-horror that brought him into the public consciousness was The Descent.

A year after her daughter's death in a car crash, Sarah (Shauna Macdonald) and five fellow extreme-sports enthusiasts find themselves lost and trapped in a previously unexplored cave system in the Appalachian Mountains.

Marshall's innovative tale of the all-female expedition soon makes them prey for the cannibalistic humanoids who live down there.

To Marshall's credit - he wrote the screenplay as well as directing - the first half of the movie is just the women pitted against the natural hazards of the cave system, and if you weren't claustrophobic going into this film these scenes are enough to make you think twice about ever considering going underground again.

The monsters don't show up until the midway point and from then on it's a brutal fight for survival, magnificently shot with various lighting gimmicks to emphasize the oppressive and terrifying situation the women are in.

One of those films best watched with the lights off and curtains closed - for the full atmospheric effect - The Descent is a superlative horror movie, on both psychological and physical levels, that just gets better and better with repeat viewings.

And for those wondering, the title also refers to Sarah's descent into madness.

Underwater (2020)

What a year 2020 was for movies inspired by the works of the father of modern horror, HP Lovecraft.

First we had Richard Stanley's incredible Color Out Of Space, directly based on one of Lovecraft's stories, and now we have the undersea action-horror Underworld, which - although not based on any particular story - certainly has a very strong connection to his broad oeuvre of cosmic nightmares.

An unexpected earthquake disrupts the integrity of the world's deepest mining operation, almost seven miles below the Pacific Ocean, in the Mariana Trench, causing the structure to start collapsing.

The few surviving crew members - including Captain Lucien (Westworld's Vincent Cassel), engineer Norah (Kristen Stewart), Emily Haversham (Iron Fist's Jessica Henwick), Laim Smith (The Newsroom's John Gallagher Jr), and Paul Abel (Deadpool's T.J. Miller) - have to find a way to safety.

With the escape pods lost, the survivors realise the only way out is to go down to the sea bed and walk to the drill head, where there are additional escape pods.

Only, they soon discover that there is "something else" in the water, something from deep below the ocean floor, that has been disturbed by their drilling.

Underwater is a phenomenal action horror flick, with an all-star cast and a genuinely terrifying scenario.

Directed by William Eubank, who brought us 2014's brilliant The Signal, from a script by Adam Cozad and Brian Duffield, there's an old fashioned quality about the movie, in that it doesn't hang around before getting to the inciting incident.

In fact, it came so fast and without warning that at first I thought Norah was dreaming, but then I suddenly realised this was real, shit was going down.

I know Kristen Stewart can be a controversial figure in some quarters, but she is magnificent in Underwater, selling her role completely and making us really care about her fate.

If you only know her from the flaccid Twilight flicks, put your prejudices aside and enjoy her cracking lead performance here.

There's no avoiding the fact that Underwater presents its horror DNA loud and proud, with obvious nods to the Alien franchise (the control room some of the characters are first encountered in looks very Nostromo-esque), The Abyss (of course), and Pacific Rim, but also films like The Descent and even 1970s disaster movies.

However, what elevates it above all - and makes it my current contender for the "film of the year" - is the monstrous Lovecraftian aspects sown into the final third of the movie.

Nothing is stated outright - it would make no internal sense to do so - but if you're a fan of HP Lovecraft's Cthulhu Mythos you'll know what's going on.

There are few better set-ups to a Lovecraftian tale than man poking his nose where it doesn't belong.

And even if you're not a Cthulhu aficionado, it's still one hell of a monster movie.

I can imagine Underwater will be a somewhat acquired taste, though, as the intense horror is heightened by the fact that for extended periods of time we - the audience - can't tell what exactly is happening, echoing the state of confusion and disorientation of the characters.

We just have to surrender ourselves, and accept that William Eubank knows what he's doing and will get us where he needs us to be to grasp the full-extent of the story.

The director is superb at maintaining the internal reality, the verisimilitude, of the dreadful situation the underwater scientists find themselves in.

And this obfuscation and vaguery only accentuates the Lovecraftian influences on this tale, with the protagonists stumbling upon indescribable entities whose motivations are wholly alien to them.

In my books, Underwater definitely demands repeat viewings and should be regarded as an instant monster movie classic