It doesn’t take much insider knowledge to imagine what the pitch session for “Rough Night” must have sounded like: “It’s ‘The Hangover’ with girls instead of guys.” Add Scarlett Johansson to the mix, and the green light must have been quicker than lightning.

The result is just the latest example of a most discouraging trend in recent American comedy—the extension of the slob comedy, which originally was pretty much an exclusive male preserve, to women. The Judd Apatow factory, of course, led the way with “Bridesmaids,” but that movie now seems positively benign compared with something like “Bad Moms,” which became a surprise smash, or now Lucia Aniello’s movie, which is, depressingly, likely to be a hit too. That it was co-written and directed by a woman, though laudable in the general sense of showcasing more female filmmakers, is really beside the point when it comes to assessing quality.

The premise is a thoroughly uninspired one (though, in fact, it was obviously prompted by several other movies desperately smashed together): Jess (Johansson), who’s about to be married, gathers with girlfriends Blair (Zoe Kravitz), Alice (Jillian Bell) and Frankie (Ilana Glazer) for a bachelorette bash that gets out of hand. Sorority sisters meeting in Miami ten years after their graduation to celebrate Jess’ imminent marriage to Peter (Paul W. Downs), they’re joined by her Australian chum Pippa (Kate McKinnon)—whom she bonded with during a college year Down Under—for a night of clubbing, guzzling ample amounts of booze and snorting plenty of cocaine before winding up with the corpse of a guy they assume to be a deceased male stripper on their hands. His death was accidental, of course—a result of chunky Alice’s overzealousness—but that doesn’t mean it won’t threaten the campaign that uptight Jess is conducting for a state senate seat, or the futures of the others as well.

Each of them, except for the wild and crazy Pippa, has something to lose, courtesy of their sketchy back-stories. Blair is a well-to-do real estate broker, but trapped in a custody battle with her ex; Frankie is a professional activist with two strikes on her record already and a three-strike law looming over her; and Alice is a teacher who could, theoretically, lose her job (though given how Bell plays her—not much differently from the way she did the guidance counselor in the recent “Fist Fight”—it’s a miracle she hasn’t been fired long before). So they try to get rid of the body, taking the movie into “Weekend at Bernie’s”-“Very Bad Things” territory until the introduction of an unexpected character—a supposed cop played by Colton Haynes—shifts the picture into a comic-action mode that ends things happily, if ludicrously. Of course, the script takes time for the inevitable sequence in which the women’s real feelings toward one another pour out to allow them to wallow in sappiness and estrangement before events lead them to embrace again.

Juxtaposed with the quintet’s adventures—which include some creepy interaction with a swinging couple next door (Demi Moore and Ty Burrell)—are the bumbling efforts of Peter, who’s convinced that Jess has called off the wedding, to drive from South Carolina to Miami nonstop to persuade her to change her mind. This section of the picture is even weirder than the main plot, portraying the prospective groom and his friends as the very antithesis of macho, having a bachelor party (a wine-tasting) that’s as sedate as Jess’s is raucous. It also involves Peter adopting what’s called the “sad astronaut” technique to get to Florida as quickly as possible, which in turn leads to a strange encounter with a cop and an even stranger one with a couple of guys at a truck stop. In theory there’s some justification to this gender-reverse tactic, which should make men as queasy as women are when they see how they’re treated in male-centered raunch-fests. In practice, though, watching a man whoring himself is no less squirm-inducing than watching a woman do so.

Johansson is more animated here than she’s been in a while onscreen, but your ability to enjoy “Rough Night” will mostly depend on your tolerance for the shtick of McKinnon and Bell. The former is actually funny in spurts, because she’s crafted a new character whose over-the-top Australian zaniness is something we’ve not seen from her before. Bell, on the other hand, is pretty much doing what she has in the past, and since Alice is a stock figure—the chubby, needy friend with a possessive streak and a pushy persona—there’s no sense of inventiveness to latch onto, nor much inclination to respond when the moment inevitably comes when we’re asked to understand her loneliness and sympathize with her empty life. (Alice even has a mother afflicted with Alzheimer’s to care for, we’re told off-the-cuff.) Glazer and Kravitz, meanwhile, are shunted into secondary roles, with the former one-note and the latter saddled with a plot thread involving Moore and Burrell that’s more unpleasant than amusing. Downs flings himself heedlessly into the part of Jess’ nebbishy boyfriend, and his natural innocence makes some of the tasteless material he has to deal with more palatable than you might expect, but that’s all relative. The craft contributions are adequate but little more, with Dominic Lewis’ score notable for trying to add punch to the slower moments.

The titular adjective is appropriate, because in the end the movie is a patchy assemblage of familiar “girls gone wild” shtick, weighed down by a dark twist that ultimately proves inconsequential and glib observations about female friendship.