Set two years before “Downton Abbey” on a wind-blown inlet along the northern coast of France, Bruno Dumont’s “Slack Bay” adds a surreal twist to the peculiar clash between the classes witnessed in Europe, circa 1910. For Dumont, who has spent his entire career wallowing in the mud and misery of this particular region (his own home turf), “Slack Bay” feels both more and less like a movie than anything the misanthropic filmmaker has done before. It’s a period piece, for one, allowing him to indulge a novel sense of pageantry. But more importantly, it’s a return to comedy for a grump who found redemption via humor in his last outing, “Li’l Quinquin,” and while this one — which landed a competition slot at Cannes — offers better commercial prospects, both in France and abroad (thanks in part to the participation of silly-acting movie stars), Dumont is still finding his feet in the genre.

Actually, comedy is just one of a multitude of genres Dumont tosses into a gumbo pot boiling over with grubby regional portraiture (his comfort zone, dating back to “The Life of Jesus”), bumbling police detective story (echoes of “Li’l Quinquin”), heightened social farce and — as the secret spice that defines the dish — tongue-in-cheek cannibal intrigue. It’s a film that, had Blockbuster Video stores not gone the way of the film’s more whimsical sartorial fancies (such as Juliette Binoche’s tropical-bird-festooned sunhat), a wisenheimer might have shelved directly between “Delicatessen” and “Deliverance.”

Dumont channels aspects of both those movies in a project that sometimes feels as if it’s being weird for weirdness’ sake, as when tubby police chief Machin (Didier Després, a partly toothless non-professional whose not-inconsiderable girth has been accentuated by a balloon-like fat suit) actually inflates and floats away. Machin and his vaguely Tintin-looking assistant Malfoy (Cyril Rigaux) serve as the connective tissue between two entirely different classes of people awkwardly thrust together in the tiny community of Slack Bay — a unique nook across the Channel from Dover, and perhaps half an hour from Calais, where well-to-do women in petticoats and parasols ramble about in ankle-deep mud, cooing about how picturesque they find the mussel- and oyster-gatherers to be.

For a local like Dumont, such bourgeois tourists (from inland Tourcoing) are a disrespectful nuisance, a bit too eagerly embodied as such by hunchback patriarch André Van Peteghem (Fabrice Luchini) and his haughty wife Isabelle (Valeria Bruni Tedeschi), looking like a human kite in her elaborate headscarves and lace-fringed frocks. The couple has returned to their faux-Egyptian villa for the season, dragging their two daughters (Lauréna Thellier and Manon Royère) and gender-amorphous niece Billie (Raph) along for the ritual. What they don’t realize is that since their previous visit, their annual vacation spot has become a crime scene. The hilariously incompetent Machin (the only consistently reliable source of laughs on offer) has been tasked with investigating a series of disappearances, and the family could well be in danger.

Not that Dumont doesn’t exploit the suspense of that situation for long. Unlike “Li’l Quinquin,” a one-of-a-kind made-for-TV black-comedy crime story that played like “True Detective” as directed by Luis Buñuel, there’s nothing particularly mysterious about the disappearances. Quite early, Dumont shows a local fisher family feasting on a far more gruesome catch as 18-year-old Ma Loute (Brandon Lavieville, a narrow-faced lad with rotten teeth and enormous oyster-shell ears) and his three brothers sit greedily around a cauldron, gnawing on fingers and other human giblets. Their weathered-looking mum (Caroline Carbonnier) emerges with a bloody limb in hand, wanting to know who wants “more foot.” Ma Loute and his father (played the actor’s actual father, Thierry Lavieville) make a modest living ferrying rich folk from one shore to the other at high tide, a ritual that causes these easily impressed ladies to squeal in mock ecstasy as these brutes carry them across the marsh.

No one would argue that these outsiders are obnoxious intruders — and Binoche’s arrival as André’s flamboyantly attired, coloratura-warbling sister Aude certainly underscores the point. And yet who but Dumont would agree that they therefore deserve to be eaten? That would seem to be the central joke in a hodgepodge of intermittently amusing comic devices, including forced pratfalls (an ever-collapsing chaise lounge), burlesque caricatures (such as Aude’s other brother Christian, played by Jean-Luc Vincent) and a wide range of silly accents and local slang. It’s a combination that works well in the hands of, say, Monty Python, though precious little translates for non-francophone viewers, apart from the general sense of anarchy.

There are scenes that come out of nowhere, as when the promising romance budding between Billie and Ma Loute is derailed by the former’s ambiguous gender identity, and others that seem to gone on forever, such as a family dinner in which much is made of carving, serving and chewing meat. None of it seems to make much sense, though it’s clear that the absurdity is no accident. Luchini and Binoche are ridiculously committed to their cartoonish roles, and though it’s logical enough for the upper-crust characters to be played by movie stars, it’s almost painful trying to watch great actors struggle to seem as eccentric as a perfectly cast non-professional. Messy as it is, “Slack Bay” looks great, with its extravagant costumes and enchanting seascapes, color-timed to give both sand and skin a peachy glow. It’s a nice alternative to the griminess of Dumont’s previous regional portraits, even if he has yet to perfect this loony new tone.

Cannes Film Review: ‘Slack Bay’

Reviewed at Cannes Film Festival (competing), May 13, 2016. Running time: 122 MIN.

  • Production: (Germany-France) A Memento Films Distribution (in France) release of a 3B Prods. production, in co-production with Twenty Twenty Vision Filmproduktion, Pallas Film, Arte France Cinéma, WDR/Arte, in association with Memento Films Distribution, Memento Films Intl., Pictanovo, Le Fresnoy, Cofinova 12, Cinemage 10, Soficinema 12, Scope Pictures, with the participations of Canal Plus, Ciné Plus, Arte France, CNC, with the support of La Région des Hauts-de-France, Mitteldeutsche Medienförderung, Medienboard Berlin-Brandenburg, German Federal Film Board, Tax Shelter du Gouvernement Fédéral Belge. (International sales: Memento Films Intl., Paris.) Produced by Jean Bréhat, Rachid Bouchareb, Muriel Merlin. Co-producers, Thanassis Karathanos, Geneviève Lemal.
  • Crew: Directed, written by Bruno Dumont. Camera (color, widescreen), Guillaume Deffontaines; editors, Dumont, Basile Belkhiri; production designer, Riton Dupier-Clément; costume supervisor, Alexandra Charles; sound, Phillipe Lecoeur; supervising sound editor, Romain Ozanne; re-recording mixer, Emmanuel Croset; line producers, Muriel Merlin, Cédric Ettouati; assistant directors, Marie Levent, Aurélia Hollart; casting, Clément Morelle, Catherine Charrier.
  • With: Fabrice Luchini, Juliette Binoche, Valeria Bruni Tedeschi, Jean-Luc Vincent, Brandon Lavieville, Raph, Didier Després, Cyril Rigaux, Laura Dupré, Thierry Lavieville, Lauréna Thellier, Manon Royère, Caroline Carbonnier. (French dialogue)