A trip to Sheffield’s stylish Showroom cinema with a good friend on a bright Friday afternoon in Spring is a happy, soul-warming time. We left the Showroom as weird jittery shells after watching a sinister, murky, discordant and worrying thriller set in a Glasgow winter..

Under the Skin is a brutally subtle and dizzyingly slow sticky seeper of a film that keeps you as entranced as you are confused.

Jonathan Glazer, a music video director and creator of Guinness’ tic-full-of-toc ‘best advert of all time’, has used his puppet-master understanding of popular culture to guarantee interest in his new film.

He has cast Scarlett Johansson as an alien trawling the streets of Glasgow in a white van picking up men and eating them.

This masterstroke has meant an intrigued audience have flocked to see a film that might have been shelved in a dusty arthouse corner and would have only received the recognition it deserves when discovered as a cult film some years later.

The first forty minutes is skin creepingly worrying as we follow Johansson’s alien in her white van driving around Glasgow’s wintry streets, coldly weighing up potential victims. Using hidden cameras many shots are of real people going about their day which adds another unsettling layer to the fear and lets the audience peek out at our familiar world from an alien’s point of view.

Pretending to be lost she asks directions in a weirdly distant and clinical English voice; once she’s established the men are solitary and alone she offers them a lift. Using some strangely alluring  alien charm she entices them to an old, derelict house and lures them into a black, dimension-less room where they slowly sink into the floor, never to return.

There are many questions building up in your head when watching this film – where has she come from? who are her helpers on motorbikes? what does she really look like? why have they chosen Glasgow? – and a large chunk of the suspense is whether or not you will find out the answers so I won’t spoil too much. But one of the things I assumed they would leave up to our imagination is the actual process of how the captured men are eaten. It was a welcome surprise when the camera seeped into the floor with one of the victims and we stayed with him, naked, while he watched her walk away above him.

What follows is one of the most effectively horrifying scenes I have ever seen. The after-glow of shocked weirdness from this scene is what created such a terrifying and bizarre aspect to the film. Without giving away too much, the victim is awake and held suspended in an eternal and gloopy void, but he is not alone..

In this ‘digestion’ scene there is an almost painful sound that accompanies the horror. The relentlessly sinister soundtrack plays a very important part during the intense first forty minutes and winds you up with discordant and jarring noises.

Another important scene involves the beautiful but emotionally clueless alien stumbling upon a tragedy on a stormy beach and not understanding why everyone is so frantic – all she wants to do is get a man in her van!

Afterwards she begins to be affected by what she has seen and a child crying in the car next to her jars a series of thoughts and emotions that gives her second thoughts about her mission.

The second half of the film is less scary but delves deeper into the uniqueness and strangeness of the alien as she starts feeling empathy for her surroundings and goes off on a little explore of Scotland, meeting different kinds of men along the way, men she doesn’t want to eat.

Surreal imagery and bizarre conversations made me smile throughout the film, but the second part involves many intentionally funny bits. Darkly twisted, these funny parts feel like they’ve been inspired by Ben Wheatley’s films, particularly Sightseers and A Field In England, which give a bit of light relief to the squirmingly tense first half.

However, rather than offering a welcome relief the second half became too tame in comparison. The physical anxiety felt from a good horror film is a fascinating feeling and in my opinion it would have been better if the visceral darkness was built to a crescendo rather than meekly disappearing and being replaced with a quirky ‘damaged foreigner goes on a holiday to Scotland where she meets the locals and discovers herself’ story.

The alien as a character becomes less interesting in this part also. Her fiercely cold demeanour disappears and she becomes weak and mopey. An encounter with a rapey truck-driver in some woods is a disappointing end.

If I was a feminist I would say that it was a shame that a strong female character became the same old damsel in distress running panic-stricken through a forest, eventually becoming a victim, but I won’t.. but someone should..

However, the second half only seems bad in comparison to the extremely effective study in suspense that was the first forty minutes or so. I understand there may be a deeper meaning to her change of heart that Glazer was trying to explore and it did give him a chance to put in some amazing shots of the Scottish scenery in the wind.

Under the Skin is a dark, bizarre, seductive and syrupy horror film that tries to grow a heart halfway through. It should be congratulated for its ambition and its uncompromising commitment to being as weird as possible.