LOS ANGELES, MARCH 24: Movie musical Chicago won the Oscar for Best Film at the Academy Awards on Sunday, but it was a pair of stunning upset victories for The Pianist — director Roman Polanski and actor Adrien Brody — that gave the biggest surprises in a ceremony marked by talk of war.

For much of this year’s awards season in Hollywood, Chicago had been a front-runner, and coming into the Oscars it was an odds-on favourite in many top categories with 13 nominations, more than any other film.

But its six awards came mostly in minor categories. And when star Renee Zellweger lost the Best Actress award to a tearful Nicole Kidman for The Hours the musical seemed to have lost its steam.

Along with Best Film, Chicago made Catherine Zeta-Jones the winner for Best Supporting Actress, and it earned Oscars in Art Direction, Sound, Costume Design and Film Editing. Brody’s victory marked perhaps the biggest upset over heavily favoured Daniel Day-Lewis of Gangs of New York and Jack Nicholson in About Schmidt, among the nominees.

Brody took the stage and gave last year’s Best Actress winner Halle Berry a big kiss. ‘‘That was better than the gift bag,’’ he said, referring to the bags that are full of expensive watches and gifts for the winners. But his jokes turned to tears as he remembered making the film and thought about the war in Iraq. He said his experiences had made him ‘‘very aware of the sadness’’ war causes.

Polanski’s victory, too, was a surprise because the director fled the US in 1978 after pleading guilty to having sex with a 13-year-old girl. He faces a long prison term if he returns and many in Hollywood have mixed feelings about him — although his peers like Martin Scorsese whom he beat consider him a film-making master.

Kidman was far less a surprise because she and Zellweger had come into the night’s ceremony neck-and-neck in the race for best actress.

‘‘Russell Crowe said, ‘Don’t cry if you get up there,’ and now I’m crying,’’ she said before turning her back on the audience. When she turned around, she apologised: ‘‘Sorry.’’

Among other winners, Chris Cooper took the Oscar for Best Supporting Actor in Adaptation, playing a poacher of exotic orchids from the swamps of Florida.

Like Brody, a nine-months-pregnant Zeta-Jones, too, found her voice cracking toward the end of her acceptance speech. ‘‘My hormones are too way out of control to even be dealing with this now,’’ she said.

Other early awards went to Spirited Away from legendary Japanese animator Hayao Miyazaki, which was named the Best Animated Feature. Popular fantasy film The Lord of the Rings: The Two Towers won the Oscar for Best Visual Effects.