The Intruder (El Profugo) is streaming in the BFI London Film Festival 12-15 October on BFI Player.

The Intruder begins with a scream. Inés (Erica Rivas) is in a studio recording the Spanish dub for an erotic Japanese horror film, a rope-bound woman’s silhouette lighting her with shocks of blue and red. She looks terrified but slyly breaks character to read her lines.

This opening scene to Natalia Mela’s second feature is promisingly uneasy, bringing to mind the sinister, mind-bending distortions of Peter Strickland’s sound booth horror Berberian Sound Studio but swapping the squelches and crunches of foley artists for a focus on the fragility of the human voice.

Inés’s voice is the tool of her trade – as well as her dubbing work she’s a soprano in an all-female choir – so it’s cause for concern when, following an ill-fated holiday, a sound engineer starts to spot background distortion on her recordings. These noises, deemed by another voice artist to be spectral ‘intruders’ who have invaded Inés’s body through her dreams, come to a head in a choir performance scene reminiscent of Irène Jacob’s stuttering collapse in Krzysztof Kieślowski’s The Double Life of Veronique.

Further sources of uneasiness come from Alberto (Nahuel Pérez Biscayart), a sprite-like organ tuner prone to disappearing and reappearing like a magician’s assistant, and Inés’s mother Marta (Cecilia Roth), one of many characters with a tendency for proposing pills as a quick fix to Inés’s problems. Intriguing as they are, with the motives for their attempted assistance unclear, neither character is given enough screen time to make a lasting impact.

The Intruder (2020)

It is Erica Rivas, perhaps best-known outside of Argentina for her show-stealing turn as a spurned bride in Damián Szifron’s satirical anthology film Wild Tales, who dominates The Intruder, as watchable and empathetic as ever. Her laughs are contagious and her fear elicits real concern. The film’s highlights are scenes of close contact between her and her sound engineer turned paranormal investigator, moments which contain a frisson of sexual tension along with the bubbling threat of terror.

What lets these scenes down is their lack of consequence. Events are strung together with hints of an overarching conspiracy but these murmurs never become a coherent voice. Leaving the audience guessing when done correctly can be thrilling, but here it feels that the filmmakers are equally in the dark.

Equally irrelevant (if entertaining) are early rom-com style scenes when Inés holidays with her unpleasant boyfriend Leopoldo (Daniel Hendler), who subjects her to bat-filled caves and cringe-inducing karaoke. Switching straight from the recording booth to this jaunt abroad is a cleverly jarring change in mood, albeit one that undermines the initial tension and makes it hard to reclaim.

It is ironic, given its focus on the vocal, that The Intruder suffers so acutely from a lack of tone. Neither committing to the horror potential of its premise (brief forays into body horror are weak and unimaginative), nor leaning into the preternatural, ethereal magic that makes The Double Life of Veronique so mysteriously beautiful, it sits at a sad middle point that is overwhelmingly mundane.