Single mother and corporate plant breeder, Alice Woodard (Emily Beecham), has genetically engineered a new species of houseplant whose scent makes its owner feel euphoric – that is, providing you give it plenty of attention in return. Worried that she spends far too much time with her ‘plant children’ than her own teenage son (after whom she has named the flower, ‘Little Joe’) she smuggles him a sapling from the laboratory as a gift. But when her son and colleagues – including would-be love interest, Chris (Ben Whishaw) – begin to behave strangely, Alice suspects her own creation might be responsible.

Little Joe is the sixth feature and first English language film by Austrian writer-director Jessica Hausner, whose penchant for the quirky and non-naturalistic is unmistakable here. Teasing a concept akin to Invasion of the Body Snatchers meets Gremlins, I was intrigued from the moment I saw the original trailer. Though I must admit that Little Joe is a little trickier to pin down than I anticipated.

Neither a full-blown horror nor a high-intensity thriller, the stakes never feel particularly high. There isn’t an overriding sense of danger as no one is harmed by Alice’s houseplants, as such. We aren’t lectured on the dangers of GMOs or tampering with Mother Nature, and the film remains relatively ambiguous about whether Little Joe’s pollen indeed carries a brainwashing pathogenic virus or not; in fact we are reminded throughout the film that this theory “lacks any sort of evidence” whatsoever. So what is the film actually about?

On the surface, sadly not a lot. The plot itself is disappointingly linear with very few surprises. But neither do we get many answers, instead much is left open to interpretation. Alice’s internal conflict and paranoia is by far the most interesting aspect of the story: at first reluctant to believe the existence of a virus, combined with the guilt that she has neglected her son the idea slowly begins to consume her. Alice’s own fears eventually pose a far greater viral threat than the alleged virus itself. The blatant irony here being that Alice designed Little Joe as a mood-lifting anti-depressant, but instead it causes her own mental well-being to deteriorate.

What mostly keeps Little Joe engaging is its striking visual style and production design. A tangible feeling of unease – that something is “off” – is maintained throughout, notably by the inauthentic colour palette, dominated by vibrant green and pink interiors, costumes and neon lights, and the nauseatingly clinical laboratory which stifles with its harsh strip lighting and scrutinous CCTV. There are moments when the camera is distracted, drifting into the empty spaces of the frame and ignoring the action altogether; our eye is drawn to the environment as much as it is to its inhabitants, thus Little Joe’s invisible airborne threat is ever-present and Hausner succeeds in making hypochondriacs of us all.

The film’s sound design is extremely unsettling. An atonal ensemble of Japanese Kabuki instruments is chaotically spliced with an abstract soundscape of high-frequency whistles, aggressive outbursts of percussion and, of course, dogs barking. It is at once exotic, mysterious and deeply disturbing – but mostly unpredictable. I won’t deny it is pretentious, and I imagine this is where many viewers will draw the line, but for me this really worked. Where the plot failed to excite, I knew I could rely on the sound to sustain my dread.

So is Little Joe all style and no substance? It’s true that the strengths lie in its stylised execution, through which Little Joe’s sinister presence permeates every shot. Bearing in mind the flower itself does virtually nothing, how Hausner manages to imply this threat from start to finish is commendable – I was thoroughly creeped out! But with no climax or dramatic pay-off to speak of, the story inevitably underwhelms. The dialogue also feels a little stiff, though it’s hard to determine if this is deliberate – like Yorgos Lanthimos’ The Killing of a Sacred Deer (2017) which intentionally flaunts its own awkwardness. The performances are mostly good, so it is a shame that the characters aren’t more interesting (I must say that Ben Whishaw’s talent seems wasted, given his character becomes an emotionless zombie for much of the film’s duration). Overall though, this is an undeniably well-crafted film and I’d say it’s worth a watch if the concept and style are of any interest you.