An engorged animal member delivers the most inspired gag, so to speak, in “The Brothers Grimsby,” a smutty but strained spy spoof in which most of the human-based comedy stays comparatively flaccid. Threadbare even by the raggedy standards of writer-star Sacha Baron Cohen’s post-“Borat” output, this tale of two estranged siblings — raised on opposite ends of the British class spectrum — reuniting to fight a global terrorism syndicate scores some stray yuks with its uneasy blend of jocular genre satire, extreme gross-out content and casually bloody, video-game-style action. Yet for all the boundaries it ostensibly pushes, the pic’s mirth-to-minute ratio is notably lower than that of last year’s sweeter-natured “Spy.” Some timely punchlines may earn these brothers a degree of fleeting pop-cultural notoriety; it remains to be seen, however, just how many HIV-AIDS jokes auds are willing to laugh at in an otherwise sparsely filled 82 minutes.

On local turf, “The Brothers Grimsby” is titled simply “Grimsby” — referring to the apparently down-at-heel seaport town in northern England that the film’s cheerfully crude protagonist Nobby Butcher (Baron Cohen) calls home. Perhaps reasonably skeptical about the American marquee appeal of a location that falls pretty low on the U.K.’s list of tourist hotspots, Sony has rebranded its product with a Grimm Brothers pun that fits neither the film’s content nor the fundamental laws of naming: The brothers’ last name isn’t Grimsby, after all. As a harbinger of the lame illogic to follow, on the other hand, the gussied-up moniker serves its purpose pretty nicely.

After taking on Kazakhstan, Austria and the Middle East in his big-screen gallery of national stereotypes, Baron Cohen has reset his satirical targets closer to home. A binge-drinking dimwit with copious misspelled tattoos, a Noel Gallagher roadkill wig and 11 variously foul-mouthed children, Nobby follows Ali G, Baron Cohen’s cult creation of the late 1990s, in sending up the supposedly vulgar lifestyles and cultural eccentricities of Britain’s disenfranchised classes. Though “Grimsby” feigns a kind of solidarity with a society dismissed by other characters as “working-class scum” — “We’re the scum that keep the ‘Fast & Furious’ franchise alive!” Nobby yells at one point in a social rallying cry — it’s hard to argue that Baron Cohen’s script, co-written with Phil Johnston and Peter Baynham, laughs with this population as much as it laughs at them, with its blithe insinuations of commonplace pedophilia and crack addiction.

In the cramped council house he shares with his raucous brood and sexually voracious wife, Lindsey (Rebel Wilson, utterly wasted), Nobby has doggedly kept one bedroom empty all along — hoping for a reunion with younger brother Sebastian (Mark Strong), from whom he was separated 28 years ago following their parents’ death. (Misty-edged flashbacks reveal the boys’ unhappy backstory with an earnestness that chimes oddly with the pic’s present-day impropriety.) It turns out that Sebastian, adopted by a well-to-do family, has grown into an MI6 agent of Bond-level urbanity and ruthlessness — an easy typecasting opportunity for Strong, then, albeit one entailing more scrotal exposure than such roles usually demand of him.

Plot machinations that can at best be described as briskly unconcerned with consequential detail engineer a farcical fraternal reunion at a London charity summit held by actress and philanthropist Rhonda George — played, if that’s the word, by Penelope Cruz, looking even less invested here than she did in “Zoolander 2.” Nobby’s buffoonery causes Sebastian to botch a planned hit on an identified assassin, instead killing the director of the World Health Organization and wounding a Somalian child AIDS activist — whose infected blood is the source of the film’s most sadistically motivated running gag. (Almost any subject is fair game for smart satire: An upshot of getting-AIDS-is-gross perhaps does not meet the latter description.)

With MI6 convinced that the luckless Sebastian is a dangerous turncoat, thus deflecting their attention from the true security threat they should be pursuing, he has no choice but to buddy up with Nobby on a globe-trotting chase that takes in a brief stop in Grimsby, before moving on to South Africa and Chile, where a mass terrorist attack is being planned at the soccer World Cup final. Besides offering Oscar nominees Barkhad Abdi and Gabourey Sidibe dismal roles as, respectively, a heroin dealer and randy chambermaid — the pic’s professed empathy with the underclasses does not, it seems, extend beyond British borders — the African interlude most notably accommodates the film’s most extravagantly conceived and jaw-droppingly executed below-the-belt set piece. Better seen than described, it’s a startling scene so extraneous to the already loose surrounding narrative that it will easily be excerpted for a long life on YouTube.

Baron Cohen’s unflinching ability to play dumb is still good for a few chuckles, making some of the film’s funniest moments out of its most innocent quips: “I could have had your life,” Sebastian tells Nobby, to which the latter gormlessly responds, “And you could have had mine.” But Nobby is a far idler comic creation than Borat, or even Bruno: Baron Cohen’s usual aptitude for elaborately transformative vocal and physical gymnastics feels half-hearted here, in service of a character type we’ve already seen abundantly lampooned in British television comedy, whether on “Shameless,” “Little Britain,” “The Catherine Tate Show” or elsewhere. The limited room for maneuvering granted the film’s female players, including the oft-uproarious Isla Fisher in a straight-woman role as Sebastian’s MI6 ally, is particularly dismaying; Cruz’s scarcely curved arc, meanwhile, is stymied by some panicked-feeling editorial transitions in the final third.

Action journeyman Louis Leterrier, not an obvious choice to direct this kind of ribald material, steers the proceedings with impersonal efficiency. The best that can be said for the film’s construction, haphazard and frappe-blended as it often appears to be, is that it ends sooner than viewers might expect.

Film Review: ‘The Brothers Grimsby’

Reviewed at Odeon Leicester Square, London, Feb. 22, 2016. MPAA Rating: R. Running time: <strong>82 MIN</strong>.<strong> </strong>(Original title: "Grimsby")

  • Production: (U.K.) A Sony Pictures Entertainment (worldwide) release of a Columbia Pictures presentation of a Four by Two Films, Working Title, Big Talk Pictures production in association with LStar Capital, Village Roadshow Pictures. Produced by Sacha Baron Cohen, Nira Park, Peter Baynham, Ant Hynes, Todd Schulman. Executive producers, Louise Rosner Meyer, Phil Johnston, James Biddle, Eric Fellner, Tim Bevan, Adam McKay, Ben Waisbren, Bruce Berman, Greg Basser.
  • Crew: Directed by Louis Leterrier. Screenplay, Sacha Baron Cohen, Phil Johnston, Peter Baynham; story, Baron Cohen, Johnston. Camera (color), Oliver Wood; editors, James Thomas, Jonathan Amos, Evan Henke, Debra Neil-Fisher; music, Erran Baron Cohen, David Buckley; production designer, Kave Quinn; art directors, Stuart Kearns, Jonathan Hely-Hutchinson; set decorators, Ute Bergk, Melinda Launspach; costume designer, Paco Delgado; sound, Colin Nicolson, Scott Harber; supervising sound editor, Julian Slater; re-recording mixers, Deb Adair, Slater; visual effects supervisor, John Moffatt; visual effects, Double Negative, Brave New World; stunt coordinators, Adam Kirley, Grant Hulley; assistant director, Alex Oakley; second unit director, Chad Stahelski; second unit camera, Fraser Taggart; casting, Lucy Bevan, Mito Skellern.
  • With: Sacha Baron Cohen, Mark Strong, Isla Fisher, Penelope Cruz, Rebel Wilson, Gabourey Sidibe, Ian McShane, Annabelle Wallis, Sam Hazeldine, Barkhad Abdi, Johnny Vegas, Ricky Tomlinson, Nick Boraine, Zak Sutcliffe, Eileen Davies.