No Country for Old Men is the most violent and infuriating film Joel and Ethan Coen have made. It’s a clever adaptation of a Cormac McCarthy story about the cruel indifference of the American west. The title is a warning that old-fashioned values no longer apply. The murder rate is enjoyably brisk, and the opening scene in the dusty Texas desert is a sensation.

A resourceful redneck called Moss stumbles across the eerie remains of a drug deal that has gone very wrong. The Mexican gangsters have shot each other to bits. Their prone bodies are starting to bloat. The air is thick with flies. A ton of heroin is stacked in the back of a pickup truck. A hopeful corpse is gripping a briefcase containing $2 million in $100 bills. The wary Moss, played with deadpan cool by Josh Brolin, ignores the drugs and walks off with the cash. The most psychotic hitman in the history of motion pictures is assigned by a mega-rich corporate giant to find the money and kill Moss. This is a return to the vintage badlands of Blood Simple for the Coens.

But this Texas is a very different country from the one they filmed in 1984. Life is infinitely cheaper. The country has been poisoned beyond repair by drugs and greed. Local codgers such as Sheriff Bell are the rare witnesses of better days. Tommy Lee Jones plays the razor-sharp cop like a punch-drunk boxer. He wears his grievances as lightly as chain mail. Sheriff Bell can identify a driver from tyre tracks in the sand, but he can find absolutely no reason to the mayhem and murders he is employed to solve.

No Country for Old Men is a sour requiem for the past, and a biblical warning about the future.

It’s also stunningly photographed by Roger Deakins. The desert landscapes are framed like paintings, and the plot hardly breaks sweat. Some things never change. The Coens never hurry their actors. There’s always time for a rueful scratch of the chin, and a long squint at the horizon.

The professional assassin hired to bump off Moss is the most absurd character the Coens have ever invented. He is bravely played by a po-faced Javier Bardem with scene-stealing weirdness. He is a satanic force of nature whose weapon of choice is a gas-fuelled bolt gun more commonly used in abbatoirs to slaughter cattle.

His most sinister feature is his hair: a classic 1960s moptop. He is an unnerving pleasure who is obsessed with destiny and coin-tossing moments that mean life or death. He is responsible for an astonishing amount of carnage.

It seems churlish to take issue with a film with such rich characters. But I lost touch with the final reel. I couldn’t picklock a meaning from the chaotic climax. It creaks with significance, but I left the cinema not entirely convinced that the glittering plaudits it has won are entirely deserved.

The supporting acts are first rate. Kelly Macdonald is terrific as Moss’s trailer-trash wife with a heart of gold. Woody Harrelson delivers a neat and icy cameo as a sharp-suited and corrupt private investigator. And Jones is in his element as the terse sheriff doomed to spend his retirement struggling with the big picture.

Cert 15, 122mins

Five bad-hair films

Robert De Niro as Travis Bickle (post-Mohawk) in Taxi Driver: fascist chic meets newborn chick

Daryl Hannah as Annelle Dupuy Desoto in Steel Magnolias: a mop of cloying curls and a dowdy twinset beneath

Bette Davis as Jane Hudson in Whatever Happened to Baby Jane?: bad-drag ringlets defy ageing

Cameron Diaz as Mary Jensen in There’s Something About Mary: is that gel in your hair . . . ?

Winona Ryder as Susanna Kaysen in Girl, Interrupted: what a lovely, er, wedge

(And no, Princess Leia does not figure – her “bagels” are hot)

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