Mountainhead review: Jesse Armstrong crafts a perfect horror film for our age

Naturally, there has always been a whole heap of anticipation for this one, but also some trepidation. Would Armstrong simply be reheating themes we've seen him tackle before, in a sort of knock-off Succession for tech bros?

The speed at which it has all been put together was also a cause for concern. The film was announced in January of this year, before starting filming in March. Now, just a couple of months later, it is about to be released.

Happily, I can reveal that any worries were unfounded – Mountainhead is a phenomenal piece of work, a thoughtful, at times harrowing treatise on our current age of technological insanity, which justifies every decision made both behind and in front of the camera.

First, the set up. Mountainhead stars Steve Carell, Jason Schwartzman, Cory Michael Smith and Ramy Youssef as a group of tech billionaire friends who – insufferably – call themselves the Brewsters.

There's Randall (Carrell), the philosophising 'intellectual' of the group who has amassed great wealth, power and connections through his work in a number of differing ventures.

There's 'Souper' (Schwatzman), so-called as a play on Soup Kitchen because he is the poorest of the group, worth hundreds of millions rather than billions. He's behind a meditation and wellness app which he is hoping to get additional investment for.

Then there's Venis (Smith), the richest man in the world who just launched a new AI product on his social media platform, which allows users to create hyper-realistic deepfake content.

Finally, there's Jeff (Youssef), the young up-and-comer whose profile is rising as a direct contrast to Venis – he has created another AI product which is able to accurately distinguish between real and fake content.

The four of them all meet at Souper's new "ugly, death-trap house" in the mountains, a Bond villain-esque lair, where they intend to spend a relaxing poker weekend and disperse some tension which has been building in public between Venis and Jeff.

However, things start to spiral as the effects of Venis's new product role-out become known – ethnic tensions flare up around the world, civil unrest is provoked and various countries' economies end up on the brink of collapse.

It's therefore a story that's both global, yet also personal and intimate, taking place almost entirely in one location and featuring very few additional characters.

This explains both how Armstrong and the team were able to get the film out so quickly, but also why. It's an incredibly timely piece, and in a world where media, tech and politics are all running at hyper-speed, it's ripped-from-the-headlines, mirror image of reality may only remain specifically relevant for so long.

For Succession fans, there are some immediate similarities here, even beyond its interest in the billionaire class.

The dialogue, for instance, is trademark Armstrong – whip-smart, cutting and, above all, laugh-out-loud funny. There are so many quotable lines here in such a short space of time, many of which rank alongside some of the best Succession ever produced.

Meanwhile, it pushes that show's basic premise that we could still engage with, and even at times sympathise with, some truly unlikeable characters to the nth degree.

If you thought Logan, Kendall or Roman were despicable, just wait until you meet these a**holes. Every one of them is almost unbearably immoral while also being utterly cringe-inducing, and their increasingly bare-bones philosophical hypothesising, coupled with their genuinely-held god complexes, makes them both fascinating as a character study but also insufferable.

Even Jeff, the apparent 'angel' to Venis's 'devil' in the AI industry, and the only one who seems even mildly perturbed by the world imploding outside their doors, is still a pretty heinous human being – he's just earlier on his journey than the other three.

It becomes clear pretty quickly why Mountainhead has been devised as a film rather than an ongoing series. Spending under two hours with these characters almost brings with it some sick level of pleasure, and Armstrong really gets to both explore their psychology, and express his own clear disdain for their philosophies, without holding back.

However, any more time and it might be difficult to sustain. If Armstrong ever wants to return to these characters and prove me wrong, then I will be seated – but I imagine he had a similar thought process, and himself found these characters too objectionable to spend 10 hours with.

All four leads are perfectly cast here, and as much as there is some character development throughout, really we get the measure of each of them from their very first scenes.

For instance, from the moment he first appears and attacks his doctor's lack of intelligence, Carrell sets out his stall, playing up the condescension and sliminess we've seen him touch upon in other, recent roles.

Schwartzman is suitably pathetic and risible as Souper, a self-debasing sycophant who has surrounded himself with people who, by sheer force of comparison, have genuinely made him believe he is in some way unsuccessful, and therefore worthlessness.

Youssef is strong in potentially the most difficult role. Jeff is in some ways the audience surrogate, the closest thing we have to a regular person in this group. But he's not that and he can never be just that, and Youssef manages to find the interesting nuances in his character to keep him equally as compelling and textured as the rest.

Meanwhile, Smith proves to be the real highlight here, playing a character who is at once the most obnoxious and outright villainous of the bunch, yet also the funniest and most exciting to watch.

Not only does he sell the moments of darkness and make the most of the comic material, but he also allows us to see behind his eyes, and understand his real internal damage, in the way that we did with the characters in Succession.

With the encroaching signs of societal collapse becoming known only via frequent news alerts, and with us stuck with some of the worst, least empathetic people possible, the first half of the film plays out like something of a modern day horror film.

Every scenario, and every blasé reaction from the group, feels disturbing realistic. Venis's cynical nihilism – "nothing means anything and everything's funny and cool" – is instantly recognisable, as is Randall's obsession with living forever via some form of internet upload.

Even more so than the Roys, these characters are so wealthy and so detached from reality, that they have nothing left to care or worry about and only the most extreme, perverse or outlandish can tickle their intrigue.

They insist they're the smartest people in the world, yet struggle to cook anything for themselves – the most basic facets of humanity are alien, or certainly disinteresting to them.

The sheer abhorrence of being in their company makes every scene feel progressively grimier and more horrible, particularly as we learn the stakes others outside of Mountainhead are facing. Some may find this off-putting, but Armstrong's wit and the strength of the performances make every scene gripping, no matter how grim.

Then, the second half takes a turn. Obviously we won't go into spoilers here, and it really is part of the fun to realise what this film is becoming as it plays out, but it's fair to say that while the tone changes and the story shifts, it doesn't get any less enjoyable.

If anything, it just gets more funny and more ridiculous, even as it gets darker and darker. (To note - this review's headline does not mean there's a supernatural twist - this isn't a Sinners or Sugar situation.)

The film's final moments don't quite live up to the rest of it – some elements are satisfyingly closed off, but it still feels like it didn't quite know the moment on which to end, or how to put a conclusive note on what has come before.

Still, it's no matter – the rest of the 100 minutes which have preceded it are so riveting and thematically rich, and take you on such a journey, that it's very hard to complain.

There will no doubt be some who accuse the film of being too over the top, too extreme and ridiculous in its satire. To my mind, that would be missing the point.

For years now the world itself has been becoming more extreme and ridiculous, in a way that the film directly addresses. There was always a question of how parody works in a populist age and a time as absurd as the one we live in.

The answer, one which more and more creatives seem to have arrived upon as time has gone on, is to match the insanity, while never succumbing to it. It's something Succession itself leant into as the seasons progressed, as have shows and films such as The Boys and Don't Look Up.

The fact that Mountainhead in many ways feels like a horror film is perhaps its greatest feat of all. As Venis notes, laughing at something can normalise it. Mountainhead is very, very funny, but it never does that.

Instead it provokes a sense of revulsion, and stays long in the mind – I haven't stopped thinking about it since.

Mountainhead will air on Sky and NOW on 1st June.

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