The Counsellor: Cormac McCarthy and the camera

Ridley Scott's star-studded adaptation of Cormac McCarthy's screenplay is released on Friday. Bitter and bleak, it's a disturbing thriller that reflects a writer who refuses to play by Hollywood's rules

Hollywood is indeed no country for old men – unless they happen to be called Cormac McCarthy, or perhaps Ridley Scott. Surely no other almost-octogenarian novelist (McCarthy turned 80 in July) could deliver a screenplay on spec to his New York agent in January and see the ensuing film go into production that very summer.

The Counsellor, directed by Scott (76 this month) and with a cast as glittering as the diamonds that bewitch its central character (Javier Bardem, Pénelope Cruz, Cameron Diaz, Michael Fassbender, Brad Pitt), opens in Britain on Friday after a US launch that has divided, baffled and disturbed critics. Without giving too much away, it's tough to convey the desolation of the final act. Suffice to say that the plot comes to resemble the slow-garrotting gadget lovingly described by Pitt's thoughtful hoodlum, "a device apparently engineered and patented in the halls of hell". Wise counsel: do not take to this movie anyone with whom you hope to share a fun-filled evening afterwards.

Early last year, the legendary literary agent Amanda "Binky" Urban was expecting to see a draft of McCarthy's 12th novel, the first (if you discount the "novel in dramatic form", The Sunset Limited) since his post-apocalyptic nightmare The Road. Instead, the script of The Counsellor – written in five weeks, apparently as light relief from fiction – arrived. Of course, with the bleakly pessimistic prophet of the Tex-Mex badlands, his notion of a relaxing digression might be closer to our idea of a protracted session with the rack and thumbscrews.

Brad Pitt and Michael Fassbender in 'The Counsellor' (Kerry Brown)

As interview-averse as ever, McCarthy has in a terse statement described Fassbender's bland, nameless lawyer as "a decent man who gets up one morning and decides to do something wrong". He opts to invest in a one-time drug deal and then return to the straight and narrow with Cruz, the fiancée he genuinely loves. Or so he fondly hopes. As in some medieval moral fable – you could think of this, in Chaucerian terms, as "The Counsellor's Tale" – the jaws of the abyss open to swallow him, inch by agonising inch.

Arguably, McCarthy's statement whitewashes the ethics of his furtive protagonist. Pitt, firing off semi-disguised literary quotations from underneath his designer stetson, tells the Counsellor that, "For all my sins I still believe in a moral order. I'm not so sure about you." As Pitt puts it in one of dozens of lines that one could bottle as Essence of Cormac: "I'm pretty sceptical about the goodness of the good."

Many viewers will assume that The Counsellor captures a smoking, bitter distillation of McCarthy. The author signed up as an executive producer, spent 40 days on the set and even advised his cast on the delivery of lines. The usual complaints about a novelist's vision being diluted via the studio system seem not to apply here – as they did, say, in Billy Bob Thornton's plodding adaptation of All the Pretty Horses or even the Coen Brothers' far sharper but whimsical rendering of No Country for Old Men. (There, Bardem sported the haircut from hell; here, as ageing playboy-dealer Reiner, it just belongs in purgatory.)

As it took the express escalator from page to screen, The Counsellor fulfilled a wish that its creator has harboured for decades. No Country for Old Men began as a screenplay, long before it mutated into a novel; so did Cities of the Plain. McCarthy's archive contains two other unfilmed scripts. The Gardener's Son did become a TV movie, while his Beckettian duologue The Sunset Limited transferred to film as a two-hander for Tommy Lee Jones and Samuel L Jackson.

Cocktail of misery: Cameron Diaz in 'The Counsellor' (Kerry Brown)

A McCarthy screenplay will never follow the Hollywood rules. But what to do about those metaphysical monologues on good, evil and the dusty borderlands in between – as much an authorial trademark as the brand on a Texas steer? Scott keeps most of them, but shortens others. He retains the Amsterdam diamond dealer's mood-setting disquisition on the flaw that defines the stone ("We seek only imperfection") but drops much of a treatise on the theological difference between the Greek hero and the Jewish prophet. More seriously, the compression of the script's concluding scenes, in which femme fatale Cameron Diaz begins to explain herself, alters the balance of moral forces. It even leaves the film open to the charge of having a "repulsive misogynistic streak" (critic Tony Dayoub's words).

True, McCarthy has always dealt in archetypes that – nudged a degree or two too far – can edge into mere stereotypes. Early on, the script describes Diaz's character as "the woman Malkina". Reiner – not the author, of course – is brim-full of macho maxims. But when a walk-on drugs-gang heavy casually says about his pitbull Dulcinea, "Siempre las mas feroces, las perras" ("always the fiercest, the bitches"), you do feel in the presence of a mind pretty much at ease with gender myths.

All the same, Malkina as written possesses a dimension that her screen incarnation tends to lose. The full script emphasises her background in Argentina ("Soy pura Porteña": pure Buenos Aires) and so helps explain the gnomic line about her parents being "thrown out of a helicopter into the Atlantic Ocean when I was three". Notoriously, that is what Argentina's military dictatorship of 1976-1983 did to dissidents; their children were often forcibly adopted by military families loyal to the junta. In their entirety, McCarthy's words do at least partly motivate a woman who believes that "When the world itself is the source of your torment, then you are free to exact vengeance upon any least part of it." Whereas the Diaz part in Scott's film will be remembered chiefly for the already-infamous scene in which she has intimate relations with a Ferrari.

In the end, McCarthy's keen paternal oversight has not saved The Counsellor from a studio makeover at crucial junctures. "At some point," the shadowy "Jefe" informs Fassbender in his pit of despair, "you must acknowledge that this new world is at last the world itself. There is not some other world." Welcome to Hollywood, Cormac. µ

'The Counselor [sic]: a screenplay' is published by Picador; 'The Counsellor' opens in cinemas on Friday