Quentin Dupieux is an endlessly interesting, endlessly frustrating filmmaker. Each of his many features has an insane high-concept idea (or several) underpinning it, illustrated using clever low-budget methodologies and a knowing wink. These are films, after all, about killer tyres, giant houseflies, telepathic jackets, and so on. They’re very funny, with a detached sense of humour – some might say “ironic,” but his films are too earnest for that – and scripts that wring quiet, uncomfortable laughs out of quiet, uncomfortable moments. They also tend to have at least one major flaw – different from film to film – that keeps them from becoming something greater than the oddball festival darlings they tend to be.

Incredible But True fits this profile perfectly. If you were to describe its plot using keywords – time travel, immortality, cybernetics – it would sound like a highly expensive proposition, but in true, credible Dupieux fashion, Incredible But True does most of its genre work via dialogue, implication, and a tiny bit of production design. It follows a middle-aged married couple, Alain (Alain Chabat) and Marie (Léa Drucker), as they purchase their first house together and discover – or rather, are cheerfully introduced to via their real estate agent – its incredible-but-true secret. In the basement, there’s a manhole, and anyone who goes down the manhole emerges on the second floor of the house, twelve hours later and three days younger.

It’s a setup worthy of a Twilight Zone episode: simple enough to describe, but with wide-ranging implications that beg to be explored. What drives people to want to be younger? How exactly does the math and timing work out? How much can you realistically de-age yourself and maintain a life? What are the physical implications of de-aging in this way? And most importantly, what are the moral and psychological implications of it? There’s a lot going on here in terms of self-image, the way society sees youth, and how those two concepts interact – not to mention the notion that outer beauty (using whatever definition you like) does not necessarily correlate with inner beauty.

This is all set against a B-plot involving Alain’s boss Gérard (Benoît Magimel), who’s dealing with his own aging in other ways, conventional and not. As he cycles through an endless succession of younger girlfriends, Alain puts to use his most prized possession: his brand-new, mechanical, WiFi-enabled penis. While the specifics of this device are unclear, with the odd hint suggesting amusing possibilities to the imagination, it’s clear how important this robot cock is to Gérard. He’s immensely proud of it, and the moment something goes wrong with it, his world begins to crumble. As a portrait of male penile obsession, midlife crisis, and the hidden emotional fragility inherent in hypermasculinity, Gérard is a hilarious counterpoint to Marie’s own attempts to recapture her youth.

For nearly all of its running time, I sat agog at Incredible But True, in awe of Dupieux’s low-budget ingenuity and utterly engrossed in the often hilarious moral conundrums at its core. With every turn, the tensions ratchet up, the comedy gets more deranged, and the ethical conversation becomes more involved. As the situation reaches a breaking point, with Marie simultaneously hitting rock bottom and making an absurd new discovery, things seem set to truly go wild. I got that thrilling feeling that a whole bunch of disparate puzzle pieces were about to come together to form a jaw-dropping picture.

And then, it just…stops.

Maybe I missed something, but I don’t think I did. Though there’s a certain poetry to the imagery on which the film ends, narratively it’s hugely unsatisfying. There’s simply a ton of juice left in the tank when the credits abruptly begin to roll – for the character arcs, thematic development, and even just exploration of the central conceit. Though I’m always in favour of short running times, this 74-minuter feels like like it probably could have gone for an extra ten, all coming at the end. As it is, the film is an incomplete statement, a very funny joke without a satisfying punchline.

And so, Dupieux continues his run as France’s most frustrating oddball director. Incredible But True is a fine and fitting addition to the house musician’s filmography. It’s funny, clever, surprising, quietly insightful – and narratively incomplete. Extremely Dupieux, then. I hope he keeps making movies like this for —