Americans perhaps make a bit of a fuss over how good the food is in Paris, but Full Phil takes this notion to ridiculous extremes. Throughout, visiting tourist Madeleine (Kristen Stewart) stuffs her face with every kind of meat, vegetable and carb while her father Phil (Woody Harrelson) is the one whose stomach miraculously swells. Meanwhile, when not bickering with her dad, she watches an ultra-low-budget black-and-white creature feature on her portable DVD player about a swamp thing with a taste for human heads, a hotel employee (Charlotte Le Bon) by her side to protect her lest Phil gets violent.

It’s all pretty much business as usual for French multihyphenate and master of his own weird self-made genre, Quentin Dupieux, back with his latest — a lean, slightly mean slice of what-the-hell-was-that fun that could be likened to what you’d get if Troma made films scripted by Samuel Beckett.

Mind you, given Dupieux’s prolific output, it’s not as if he was away for long. He released The Piano Accident only last year, and The Second Act the year before, although admittedly that’s a slightly slower pace compared to the two-films-a-year output he once achieved. This one marks a slight switch-up because he’s working with American actors again for the first time in a while. (The last effort was probably Wrong Cops in 2013, if you don’t count shorts and music videos with the likes of Charli XCX.)

Arguably, this features his most A-list cast ever, and Dupieux rewards their trust in him by assembling a script that feels a bit more polished than usual — a surrealist tale with a proper ending for a change, although we’re not exactly talking Guy de Maupassant or Flannery O’Connor levels of narrative elegance here. The utterly silly B-plot, for instance, really feels tacked on to pad out the running time, perhaps an exercise that was meant to be another project that didn’t so willfully waste the talents of Emma Mackey, who gets a stumble-on part as the monster’s first victim. Her distressed screaming is a gas, at least.

The main meal is, of course, dished up by Stewart in a rare purely comic role and Harrelson in his more expected form, in both cases broader and a little less polished than feels entirely comfortable. Neither of them convinces that they entirely get Dupieux’s joke, or are even sure that the joke isn’t on them too. As with The Second Act, which sent up cancel culture, there’s a slightly reactionary vibe in the way the script has Stewart’s Madeleine represent a distinctly millennial kind of passive-aggressiveness. As she sits in their hotel suite, stuffing her face with platter after cloche-covered platter of room service food, she keeps flipping the script back on her dad every time he gets angry or dares to protest the decision by hotel employee Lucie (Le Bon from The White Lotus, quite hilarious) to insist on staying in the room in case he attacks Madeleine.

Phil, meanwhile, reads as a French stereotype of a squeamish, hygiene-obsessed, prissy American, so consumed by shame over the fact that Madeleine clogged the toilet in his half of the suite that he won’t let maintenance come fix the blockage, perhaps because they think it’s his excrement and not hers. “Everybody shits, dad,” she counters with understandable if excessively peevish exasperation, pointing out that the maintenance people don’t mind working with the stuff in toilets anymore than hairdressers mind touching heads all day. With a long history of semi-estrangement suggested between the two, they can’t come to any agreement over the toilets. So they move on to sniping about Phil’s desire to work on their impaired relationship, which Madeleine dismisses, calling it the part where he “regurgitates all your shrink’s bullshit,” a telling choice of words.

Stewart is perhaps at her best when dishing out these bratty, bitchy lines, with a snarkiness that’s she’s clearly having fun with. Similarly, for someone whose fashion sense, insouciant air of coolness and physical appearance have been a fetish for the public ever since she went supernova with the Twilight movies, she seems to be enjoying messing with that elegant, Chanel-clad image here, stuffing her gob constantly, holding greasy steaks by the hands and gnawing the meat off the bone. The effect is like an anti-anorexia infomercial.

But as the film goes on, the archness cools down a bit and there’s a weird, genuine poignancy in a speech where she tries to have a rapprochement with Phil, who by the end of the film looks like he’s about to give birth to twins, so distended is his belly with food. Fans of Monty Python’s The Meaning of Life may start to have uncomfortable flashbacks to the fate of Mr. Creosote, who had just one wafer-thin mint too many.

Who can say for sure what Dupieux is trying to say here. Something, it would seem, about how love and food and family feeling can turn monstrous, a point echoed weakly in the dumb B-movie starring Tim Heidecker and Dupieux-buddy-of-old Eric Wareheim. Meanwhile, there’s a genuinely funny running gag about how oblivious American tourists are to what’s going on locally in the countries they visit. Phil steps outside the hotel for a cigarette, utterly unfazed by a riot going on all around that includes a burning car in the background and armored French police beating the crap out of protesters with batons. Later, someone throws a Molotov cocktail at the taxi Phil and Madeleine are taking to a restaurant, and the taxi driver just sighs and suggests it would be faster if they got out and walked given the effect on traffic. Haven’t we all been similarly inconvenienced on vacation?

Some may see in the final gore-splattered climax a simply expedient way to wrap things up, but both Stewart and Harrelson’s performances — all in by this point, or at least tonally in tune with Dupieux’s antics — somehow sell it all emotionally. The spooky, rumbling electronic score by Siriusmo (German EDM producer Moritz Friedrich) really bolsters the atmosphere of whimsy, weirdness and a tender sort of melancholy, a combination that’s uniquely Dupieux-ian and all the director’s own.