Not that long into Hereditary, something truly horrible happens.

It’s sudden, brutal, and left viewers at my screening with their hands pressed to their mouths in shock. For a few minutes afterwards, I was fully expecting a fake-out: most horror films wouldn’t go through with such a momentous piece of nastiness so early on. A dream sequence, perhaps, a hallucination? But there’s no fake-out. Nor, from then on, is there much respite from the nightmarish fear which pervades Hereditary. As the early shock demonstrates, the film refuses to follow the standard horror-film beats which let the audience know when to relax and when to tense up. Instead, it’s tension throughout. A contemporary cross between The Exorcist and Rosemary’s Baby, but scarier than either, Hereditary is the most frightening and well-crafted horror film I’ve seen for years.

It’s the first feature film from director Ari Aster, and the latest in the current cinematic horror renaissance. It opens on the day of a funeral: that of Annie Graham’s (Toni Collette) mother, a strange and secretive woman who, at the end of her life, shared the house with Annie, her husband Steven (Gabriel Byrne), and two children Peter (Alex Wolff) and Charlie (Millie Shapiro). At a grief-counselling circle we learn that Annie had a troubled relationship with her mother, Ellen; among other things, she was uncomfortable with the bond between Ellen and her daughter Charlie. Charlie, we have already discovered, is a strange thirteen-year-old girl, prone to making artworks out of animal parts and drawing unsettling images in her sketchbook. Perhaps, we wonder, Ellen’s influence has not died with her. That’s about the limit of what you should know going in: the shocks and revelations of the next couple of hours deserve to be experienced with as few expectations as possible.

As seasoned horror fans will be aware, there are many different kinds of fear a film can evoke. There’s the creeping dread of anticipation; the pulse-racing terror as victims flee a pursuer; the quiet horror of what the hell is that thing in the corner of the room; the horrified disgust at a bodily mutilation; the burst of fright from a jump-scare. Hereditary doesn’t limit itself: it has pretty much everything in its frightening box of tricks. Furthermore, they’re all effectively delivered. Watching Hereditary in the cinema is a physical experience in a way few films achieve: my muscles were often tensed up, my hand flying to my mouth or to cover my eyes, my face turning away from the screen. The experience is reinforced by other audience reactions – the screening was full of gasps and muffled squeals. It’ll be interesting to re-evaluate the film on the small screen, to see if its terrors are replicable on TV.

grief, rage, pain are all conveyed with gruelling realism by the film’s excellent cast.

The emotional effectiveness of Hereditary isn’t limited to its overt horrors, however. Equally harrowing are the scenes of more everyday family conflicts – a family row mid-film, which could be lifted from a conventional drama, was almost as tense and upsetting as the film’s supernatural sequences. Similarly, there were audible gasps from the whole cinema at something Annie says later to her teenage son; something no child should have to hear from a parent. The impact of the horror scenes, too, is reinforced by the authenticity of the human emotions behind them: grief, rage, pain are all conveyed with gruelling realism by the film’s excellent cast.

Collette is given the opportunity to indulge in some classic horror-film histrionics – comparable to Essie Davis’s performance in The Babadook – and delivers them to great effect; Byrne’s quieter performance is a nice counterpoint to her operatic display. Throughout the film the actors make us care about their characters: when, at the height of the terror, Annie desperately tells Stephen that he’s the love of her life, we believe her – and it brings a lump to the throat even while tensed up with frightened anticipation. Wolff and Shapiro shine as the teenage siblings: Wolff bringing a delicate vulnerability to his pot-smoking high-schooler and Shapiro both sad and unnerving as his troubled sister.

The film’s frenzied climax verges on the overblown, with scares and lore coming thick and fast.

As with most good horror films, Hereditary has a lot going on thematically: there are plenty of metaphors and symbolism for those who go looking. The film has something to say about mental illness, family dynamics, gender: like The Babadook, Hereditary is particularly interested in troubled motherhood. Unlike some recent horror films, however – Under the Shadow comes to mind – the symbolism isn’t pushed to the fore intrusively. There’s a lot to be explored, and I look forward to reading the critical analysis Hereditary will generate, but it’s equally enjoyable for audiences who just want a scary ride. And what a ride it is!

The film’s frenzied climax verges on the overblown, with scares and lore coming thick and fast. In a lesser film, it might be almost risible, but Hereditary just about pulls it off. It has earned it through its exceptional craft and artistry throughout. Taking many elements from the hokiest of horrors (big shadowy houses in the woods, ill-judged seances, nastiness in the attic, occult tomes) Ari Aster shapes them into something a cut above the rest. Backed up by an unsettling score, uncanny camerawork, and editing which supplements the film’s nightmarish qualities, Hereditary is a must-see for the most jaded horror devotee – although more sensitive viewers should take caution…