Michael Angelo Covino’s “Splitsville,” a film written along with his co-star, Kyle Marvin, is a French sex farce in American drag — or so a friend suggested after leaving a press screening. The auteurs might demur, citing as inspirations Italian sex comedies like Lina Wertmuller’s “The Seduction of Mimi” (1972) and Pietro Germi’s “Seduced and Abandoned” (1964). Splitting the difference for “Splitsville,” let’s say that Messrs. Covino and Marvin tap into currents that are European in their sense of moral suasion.

This may be the reason why their film is, at its core, a mite forced. The ability of Americans to shuck their puritan heritage, however occluded we might believe it to be, has proven difficult: Old roots die hard and all that. Which isn’t to say that “Splitsville” doesn’t succeed at generating a consistent level of bemusement or occasioning laughter. There are moments here that are as outrageous and uproarious as they’re intended to be. Still, a strain of conservatism wheedles its way through the proceedings.

Just how this wheedling is made evident risks spoiling a denouement that is, if not altogether surprising, then politic to hold back on all the same. Given that the film keys into a cultural moment when polyamory carries a high profile amongst our chattering classes, no multi-partnered plot point is guaranteed. Having said that, “Splitsville” works on premises that are well burnished — Molière might have appreciated the film’s sense of folly, P.G. Wodehouse its intricacies of plot, and Noel Coward the deliciously underplayed quips. Messrs. Covino and Marvin do well by these forebears.

Ashley (Adria Arjona) and Carey (Mr. Marvin) seem like a loving couple. We meet them as they’re driving along a two-lane highway, proving themselves tone-deaf as they sing along to a favorite tune. They’re practically newlyweds — the couple have been married a year-and-a-half. Ashley is giddy enough in her connubial bliss to engage in a bit of hanky-panky while her husband is at the wheel. This opening scene, cute and endearing, is brought to an abrupt halt when Carey’s driving skills are put to the test. This won’t be the first time “Splitsville” is punctuated by a spectacular set piece.

Ashley subsequently reconsiders the state of their marriage. Admitting to Carey that she’s been unfaithful, Ashley asks for a divorce. Remember: Our couple are still on the endless highway, albeit now pulled over on an embankment. A tense discussion, played with exquisite comic timing by Ms. Arjona and Mr. Marvin, leads to Carey stepping out of the car and then running, willy-nilly, through this brush, that pond, the stray backyard, and, finally, into a clearing by a seaside home in which a copacetic woman is shaping a bit of clay.

Meet Julie (Dakota Johnson), a ceramicist by trade and wife of Carey’s best friend, Paul (Mr. Corvino). Carey tells his friends about Ashley’s request for a divorce, a discussion that leads to a revelation that the secret to a happy marriage — or, at least, Julie and Paul’s marriage — is having an open relationship. “Don’t ask, don’t tell” is the watchword, though Julie has a good idea what Paul is up to on his constant late-night ventures into the city. High-end real estate deals are the rationale for these trips, but we know what business Paul is really engaging in. Or do we?

From that point on, our couples reckon with their infidelities in ways that, though leavened by moments of tenderness, are sometimes absurd and, at their best, raucous. An extended fist fight between Carey and Paul is a jaw-dropping high point: Rarely has screen violence been ladled out in a manner that is as galumphing as it is extreme. Hilarious, too, is the scene where a host of goldfish meet their great reward at an amusement park. Look, too, for Nicolas Braun, late of “Succession,” in the role of a mentalist performing for a tough audience.

A nagging question remains: How on earth did two less-than-stellar examples of manhood end up with women as gorgeous as Ashley and Julie? Well, they wrote the script, that’s how, and if “Splitsville” is the price beauty pays to comedy, then Messrs. Covino and Marvin have earned their keep.