Bigelow, Bridges and Bullock are best in show at the Oscars

Like a well-made film, it all went according to the script: Kathryn Bigelow scored a historic first for female film-makers, and an eagerly anticipated David and Goliath-style battle saw the little guy triumph as The Hurt Locker walked away with six trophies and most of the headlines at the 82nd Academy Awards in Los Angeles.

Ms Bigelow finished the show on-stage, after her Iraq War thriller was named Best Picture. But it was her victory in the previous race, for Best Director, that marked the night's most significant moment: film is often called a director's medium, and the 58-year-old film-maker is the first woman to walk away with the Oscar.

Her achievement, after 81 years in which female directors have managed a grand total of four nominations, came at the cost of the most appropriate of rivals. James Cameron, the director of Avatar, the blockbuster that lost out to The Hurt Locker in several categories, just happens to be Ms Bigelow's ex-husband.

"There's no other way to describe it, it's the moment of a lifetime," she said, after winning the award. "I hope I'm the first of many [female best directors], though I love to just think of myself as a film-maker, and I long for the day when the [female] modifier can be a moot point."

The result at Sunday night's ceremony was also a triumph for the film itself. The Hurt Locker, a little-seen independent movie about a bomb disposal squad in post-invasion Iraq, was made on a budget of $15m (£10m). By contrast, Avatar cost around $300m, and has generated $2.5bn at the box office, making it the most lucrative film ever produced.

Pundits expected The Hurt Locker to be the night's big winner, since it had already been honoured at most of the preceding events this awards season. The film's other Oscars were for Best Editing, Best Sound Editing and Best Sound Mixing. Its writer Mark Boal, a former journalist who came up with the tale while embedded with US troops, won the award for Best Original Screenplay.

On a night when almost every prediction came true, all the acting awards ended up where expected. Odds-on favourite Jeff Bridges won Best Actor, for his turn as alcoholic country music star Bad Blake in Crazy Heart. Sandra Bullock was named Best Actress, for playing a Southern housewife who adopts a homeless youth and helps him become an American Football star in The Blind Side.

Ms Bullock was a popular choice with the public, who helped the film defy mixed reviews to make $250m, and one in the eye for critics who have sneered at some of the commercial fare on her professional CV. Just 24 hours earlier, she was named 2010's Worst Actress at the Razzie Awards for All About Steve.

"Did I really win this, or did I just wear y'all down?" she asked, upon becoming the first person to win an Oscar and a Razzie in the same year. Backstage afterwards, she added that the two trophies will be displayed together. "In the entertainment business, you take the good with the not so good. It's the great equaliser. You know, nothing ever lets me get too full of myself. So they'll sit side by side in a nice little shelf somewhere, the Razzie maybe on a different shelf, lower," she said.

Christoph Waltz, an Austrian actor previously unknown outside Europe, won Best Supporting Actor for his portrayal of a Nazi officer in Quentin Tarantino's Holocaust fantasy Inglorious Basterds. The comedian Mo'Nique (real name Monique Imes-Jackson), won Best Supporting Actress for playing an abusive mother in Precious.

In other categories, the Pixar film UP won Best Animation, as was widely expected, and Best Original Score, continuing the CG animation studio's impressive performance in the Academy Awards. The three wins for Avatar which, like The Hurt Locker, had been nominated for nine awards, came in technical disciplines.

A note of controversy was added to proceedings in the Best Documentary category: The Cove, about the Japanese dolphin-fishing industry, has enraged Japan. Best Foreign Film went to Argentina, for only the second time, with victory for Juan José Campanella's Spanish-language thriller El Secreto de Sus Ojos.

After years of struggling with sliding television ratings, the Oscar show's organisers experimented with an old-school style of ceremony presented by Alec Baldwin and Steve Martin. Although it drew mixed reviews, and began to sag towards the end of its three-and-a-half-hour run, initial figures suggest that ratings rose by around 10 per cent, to more than 40 million viewers.

But if the show went down well with its American target audience, it was not such a good year for the British, who had a notably poor crop of awards. The Wallace and Gromit animator Nick Park lost out in the Best Animated Short category, the first time he has not won an Oscar for which he has been shortlisted.

Carey Mulligan, the star of An Education, was overlooked for the Best Actress award, along with the BBC film's screenwriter Nick Hornby for Best Adapted Screenplay. Armando Iannucci and his co-writers did not win anything for the political satire In the Loop, and Colin Firth missed out on Best Actor.

The UK's only winners were Ray Beckett for Sound Mixing on The Hurt Locker and Sandy Powell, the costume designer for The Young Victoria, who has now been nominated for a total of seven Oscars, and has won a hat-trick of them. "I've already got two of these, so I'm feeling greedy," she joked.