When a young woman with a troubled past and a nightmare family meets a handsome stranger, she experiences the heady rush of liberation – new-found self-confidence along with the possibility of love. But could her perfect new man be, in fact, a monster? And an even more disturbing question: would she care?

Beast is a sure-footed, white-knuckle psychological thriller, inspired in part by the gruesome real-life exploits of the Beast of Jersey, a sex offender who terrorized the island in the 1960s. It’s an auspicious feature debut by writer/director Michael Pearce, with an absolutely sensational performance by its star, Jessie Buckley.

It’s also the second big screen outing for the Channel Islands in a week – though after the feel-good vibe of The Guernsey Literary and Potato Pie Society, this is far darker, more troubling fare.

As a serial killer is raping and murdering young Jersey women, the community is attempting to continue life as usual. Unfortunately for the insecure Moll (Buckley) that means a pretty miserable existence: under the thumb of her tyrannical mother (Geraldine James), in the shadow of her big sister, with a humdrum job as a tour guide. Even the potential relief of singing in a local choir is tarnished by the fact that mum is the conductor.

After a drunken night at a club, Moll is rescued from a potential rape by Pascal (Johnny Flynn). A labourer and poacher with doubtful hygiene, her saviour is certainly a strange fellow. But he’s also handsome, charismatic and just the sort of working class outsider who would offend Moll’s uptight family. Falling for him is the spur she needs to break those suffocating family bonds.

And yet on the same early morning that Pascal was alone on the beach, in time to come to Moll’s aid, another girl was abducted. Soon he is a police suspect.

This could be just another story of a prince charming proving to be the big bad wolf. However, Pearce constructs so much ambiguity and slow-burn tension that he elevates his scenario completely. Pascal may or may not be the killer. Meanwhile, Moll comes with her own dark history (“You’ve come so far Moll,” her mother tells her mysteriously) and a temperament that teeters on the edge of breakdown. Being with Pascal is liberating, but defending him from suspicion threatens to unleash her own demons and sets the community against her too. It’s impossible to second guess where any of it will lead.

Buckley has been making a strong impression on television for a while now – stealing the show as Marya Bolkonskaya in War and Peace, holding her own against the formidable Tom Hardy in Taboo, and currently starring in The Woman in White. A star in the making, she’s mesmerising here as a deeply troubled young woman, not quite heroine or victim, but a flaming haired powder keg of emotions who is just as perplexing as the man accused of being a killer.

Alongside her, Flynn skilfully keeps us guessing about Pascal – he’s at times absurdly likeable, at others allowing the possibility of a sick mind behind the cheeky facade. The actor and musician has been more notable to date on stage than screen, particularly alongside Mark Rylance in Jerusalem and as another challenging stranger in Hangman; like Buckley, we’ll be seeing a lot more of him.

Hailing from Jersey himself, Pearce evokes that trusty dramatic dichotomy – a beautiful island and its ugly community. Moll and Pascal are pitched against a conservative, bigoted bunch who hardly elicit sympathy, despite the crimes perpetrated on their young. The result is morally complex and highly rewarding.

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Avengers: Infinity War (12A)

Apparently, all the Marvel films over the past decade have led to this, the 19th in the juggernaut movie franchise – and the biggest, boldest, most superhero-packed of them all. Until the sequel, anyway. A film that brings together The Avengers, Dr Strange, The Guardians of the Galaxy and the entire world of Black Panther could easily buckle beneath the sheer weight of characters and self-importance. Yet directors Anthony and Joe Russo pull it off, just, with an action fantasy epic that is both darker and funnier than expected, and surprisingly light on its feet. It helps to have a great villain, Thanos, a man mountain intent on destroying the universe, who Josh Brolin lends extraordinary nuance. And some of the superhero team-ups work well, especially Robert Downey Jr’s Iron Man with Benedict Cumberbatch’s Strange (the brightest sparks), and Thor with the Guardians (the cheeriest). The special effects are spectacular, if typically exhausting, balanced by bitter-sweet love, unexpected deaths, even pathos. Unlike the genre-busting Black Panther, Infinity War is for Marvel fans only. But they have much to marvel at.