Want to see Peter Dinklage dressed like a Juggalo and waving an Uzi? Macon Blair’s follow-up to The Toxic Avenger is full of surprises like that, a goofily violent stoner romp-slash-caper that likely would have been called Coenesque back in the not-so-distant past. Dumb and Dumber meets Midnight Run better reflects the premise; despite the abrasive, sweary title, The Sh*theads is actually a really rather endearing buddy movie, with O’Shea Jackson Jr. — looking the very image of his father — and Dave Franco as two sad-sack losers thrown together by circumstance and pitched against a very formidable foe.

Davis (Jackson) is the first of the duo we meet, being hauled over the coals by a priest for his ill-thought-out decision to take a busload of parishioners’ children to see, of all things, Lars Von Trier’s Antichrist. That was his first strike, the second — and, for the priest, the kicker — is that he didn’t pack up the kids and leave even after the first instance of unsimulated sex (“You saw a dong and you stayed for the rest of the movie?”). Cut to Mark (Dave Franco), a less-than-model employee who sits at his desk vaping, drinking coffee laced with bourbon and watching scuzzy betting show Scum Brawlz on his computer screen.

Both are immediately relieved of their responsibilities, but Davis has a second job, which is how he pairs up with Mark, working for a company run by a woman named Dorindo. This is her side hustle, as we find out in one of the film’s many funny sight gags, and it involves ferrying disturbed young people to rehab. Mark thinks this means “psychos, junkies and sh*t”, but Davis is more empathetic. “Just follow my lead on this,” he says. “You’re not a cop or a bounty hunter.”

Using Mark’s beat-up car, their first assignment is Sheridan Kimberley (Mason Thames), heir to a vast business fortune and suffering from “emotional issues” as a result of his parents’ divorce. Sheridan is a major piece of work, and it’s a while before we realize just how stupid Davis and Mark are; he’s a famous — no, notorious — YouTube prankster whose criminal antics are covered up by his rich family (“That kid’s a f*cking legend,” a passer-by later notes). A mysterious puncture means a new tire must be acquired, since Mark is naturally too dim to drive with a spare, and so the three check into a motel for the night. Which is where the story really begins, once Sheridan finds Mark’s formidable drug stash.

Followers of Blair’s career will immediately see comparisons with his earlier acting work in the two films he made with Jeremy Saulnier (2013’s Blue Ruin and 2015’s Green Room). But if Saulnier has taken a slightly more straightforward genre route since then, Blair has marshalled those very same neo-noir tropes down an altogether more anarchic road, and it’s to his credit as a screenwriter that the shaggy-dog nature of the story always feels organic not matter how outlandish — not to mention scatological — the digressions become.

Casting could not be better; Franco has played this kind of charmingly naïve and likable wrong ’un before, but it’s a role he plays well — Mark is a loser who doesn’t realize he’s even lost and whose life advice to Sheridan is rather telling (“Sometimes you gotta eat shit; the trick is not to ask for seconds”). Star of the show, however, is Jackson as Davis, the gentle giant, a Godly man who means well but harbors an explosive temper, and the entire film is peppered with his earnest apologies, the most memorable being issued to the motel manager for insulting him with the best yo’ mama joke ever (“Yo’ mama was an extra in Labyrinth!”). Between these two big personalities, Thames fits in perfectly, a seemingly nondescript rich kid who turns out to be a chillingly amoral agent of chaos.

It would be a stretch to interpret Sh*theads as a biting political satire, but, like Adam McKay’s The Other Guys, there is a definitely strong and very intentional vein of social comment here. In fact, it covers two very real current trends, one being the rise of the internet troll, whose antisocial antics — like the infamous Johnny Somali — are invariably at the expense of normal working people. The other, and much more subtle, is the rise and rise of bribe culture in today’s pardon-happy America, where money talks and felons walk. When you look at the world like that, people like Davis and Mark are the salt of the earth, which, on reflection, just might be a better description of them than the sh*theads.

Title: The Sh*theads
Festival: Sundance (Premieres)
Sales: WME/CAA
Director/screenwriter: Macon Blair
Cast: Dave Franco, O’Shea Jackson Jr., Mason Thames, Kiernan Shipka, Nicholas Braun
Peter Dinklage
Running time: 1 hr 40 mins