Cannes round-up: War, revolution, love, death ...and Liverpool

Cannes was long on big themes and short on levity but there were some gems, not least a hymn to home by Terence Davies

We knew this year's Cannes would be heavyweight – but who knew it would be heavyweight like this? "Leaden" is perhaps too damning a word; let's settle for "earnest". There's been a steady flow of high-quality films in competition, but a heart-numbing lack of joy, levity or just plain surprise. Bizarrely, this year the critics are in polite agreement about just about everything; that perennial headline "Cannes row sets the Croisette aflame" is one that, for once, you won't be reading.

However, the competition did contain one head-scratcher and one passably ludicrous clunker. The head-scratcher was The Headless Woman, by Argentina's Lucrecia Martel, who made the superb The Holy Girl. Her new film is a puzzler of hypnotic opacity about a woman who accidentally runs over a dog, and possibly a person too, but she's not sure, and neither am I. My notes on this film basically consist of a field of question marks, but there's certainly something going on here. But I'll pass comment on what till I've seen it again: frankly, I can't wait.

The dud – which raised gales of boos at the press screening – was Frontier of Dawn by the French veteran Philippe Garrel, a farrago of love, death and romantic posturing, which ought to win the director's son, heartthrob Louis Garrel, some sort of special award for Best Sulking, or perhaps Stormiest Brow.

It's not been a good year for the US big-shots. Clint Eastwood's 1920s-set Changeling was a torpid period piece. Angelina Jolie, in a shameless bid for Oscar-night prestige, plays a single mother whose young son mysteriously disappears. When the corrupt LAPD try to palm her off with another boy, she rebels and runs foul of the powers that be. Self-important, over-designed and veering awkwardly into killer-chiller territory, Changeling was as pallid as its sepia colour scheme.

The other American monolith was Che, Steven Soderbergh's portrait of the revolutionary hero – a diptych screened here in a single, punishing, four-and-a-half-hour session (some of Fidel Castro's speeches are shorter). Che was not quite the ordeal one dreaded: with Benicio del Toro as a soft-spoken, affable Guevara, this was in no way the bloated hagiography that, say, Oliver Stone might have given us. Instead, it was a measured, fastidious attempt to evoke the procedures of guerrilla warfare – Soderbergh's attempt to emulate that ne plus ultra of political war film, The Battle of Algiers. Part one covers Guevara's part in the Cuban Revolution, while the considerably more challenging Part Two traces his catastrophic attempt to achieve revolution in Bolivia – a year-long episode that at moments felt as if Soderbergh had shot it in real time.

You have to admire Soderbergh's courage in making one of the most uncommercial, and politically contrary films ever attempted by a Hollywood director. Che is an admirable achievement but an altogether quixotic one, that I can't imagine anyone actually enjoying.

At time of writing, the competition still has a few more films to go, but one of the best so far is Adoration, by Canada's Atom Egoyan. After coming unstuck in recent years, Egoyan is back on vintage form with a complex multi-strander about a high-school student who spins a story about having a terrorist father. Challenging and intricately worked, Adoration interweaves themes of identity, self-deception, bigotry, internet culture and post-9/11 anxiety. It's a lot to take on, but the mix brings out the best in this genuinely cerebral director, who here gives us more intellectual grist than just about anything in competition.

This festival's big surprise has been a sudden renaissance in British art cinema, its centrepiece being the long-overdue return of neglected maestro Terence Davies. His Of Time and the City, shown out of competition, was a tender poetic essay about Davies's native Liverpool, with archive footage set against the director's voice-over tissue of memories, confessions and acerbic humour.

This is not the Liverpool you're used to: when Merseybeat happens, Davies admits he never liked the Beatles, and plays us some classical music instead. It's a true auteur film, 100 per cent personal, and trumpets the return of one of the UK screen's true individuals.

As for new discoveries, the film that absolutely grabbed me by the throat was Johnny Mad Dog, by the French director Jean-Stéphane Sauvaire. It's a brutally aggressive drama about a detachment of child soldiers, leaving a trail of carnage in an African war zone that could be (but isn't necessarily) Liberia, where the film was shot.

Brutal in style as well as content, the film casts children and adolescents who have actually lived through the horrors depicted. This undeniably leaves Sauvaire open to the charge of exploitation, but his intense, unnerving film finds an arresting way to say something new about the horrors of war.