Horror is a genre whose audiences have a hyperactive desire to discover the next great film. Perhaps it’s the visceral reaction the genre provokes that drives this hyperactivity. Regardless, it feels that we’re always eagerly searching more than in any other genre – diamonds in the rough as the old adage says. Sadly, South Korean director Jason Yu’s horror film Sleep is far removed from being one of those.

Yu’s feature debut about soon-to-be parents Hyun-su (Lee Sun-kyun) and Soo-jin (Jung Yu-mi), whose peace is disturbed when his sleepwalking escalates into extreme nocturnal behaviour, mixes up life and art. Sleep, also has the vibe of a commercial American horror film, and the less notable J-horror entries. Yu’s attempts to articulate a specific dialect of cinema is uneven, and Sleep may be that common faux pas of an early draft of the script hastily thrust into production.

Sleep starts off well, introducing us to the characters and setting up what seems to be a suspenseful supernatural horror. Yu quickly pivots away from this, but it never feels misleading. Instead, it’s a natural trajectory of the story. Sleep appears to want to emphasise the sense of despair and chaos of the couple’s troubling circumstances over nail-biting supernatural horror, yet it frequently finds touches of comedy that sometimes leans towards black humour. Where Sleep comes undone is Yu’s languid approach to the narrative and character, and the casual use of comedy, that positions it as an afterthought.

Soo-jin’s lack of development is the most striking, whose journey begins with her as a happily married woman unsettled by her husband’s sleepwalking, to experiencing invasive feelings of despair and anguish, and the raw and visceral survival drive of the feminine and the maternal. Soo-jin is the beating heart of the film, dragging the story into the violent tradition of the genre, that teasingly recalls the violence of Abel Ferrara’s 1979 black comedy horror, Driller Killer. It’s far more inference than actuality, but Sleep still possesses a visceral and vicious spirit in its supernatural culmination, that pushes a woman towards breaking point.

The film is split across three chapters, and until part way through the first, when there’s a possible explanation for the inexplicable nocturnal behaviour, Sleep is well plotted. It’s at this point that Yu struggles to thread together this answer with Soo-jin’s support of her husband, despite her growing anxiety. In the heightened episodes of the drama, Hyun-su is locked in the bedroom at night to stop him from sleepwalking around the apartment, and in one nighttime scene, Soo-jin takes refuge in the bath

Sleep, however, quickly becomes clichéd with its pedestrian plotting. Yu struggles to creatively engage and Soo-jin drifts the rest of the way through a story that is missing an engine of ideas and themes, that would give it weight and resonance.

Korean cinema is known for painting with broad brush strokes by creating hybrid-films. It’s difficult not to sense that Sleep is also encumbered by being caught between worlds. It struggles to thread together genres – does it want to be more of a mystery, supernatural thriller or suspenseful horror? It never manages to answer this question and another concern is that it’s a short film that Yu has stretched beyond its limitations.

The concept of sleepwalking and night terrors is fertile terrain for the horror genre. These are familiar beats and ideas that our fascination with endures. They tease and tickle our imagination, but in the context of Sleep, its filmmakers become a mirror image of the antagonistic force disrupting Hyun-su and Soo-jin’s tranquility, by wasting our interest in its naturally captivating conceit

Sleep premiered in the 32nd edition of Raindance, when this piece was originally written. In cinemas on Friday, July 12th. On VoD on August 19th.