It takes a continent

'Australia' harbors ambitions that match its sweeping panorama and epic romance

Baz Luhrmann has named his new movie after a continent, which should give you a clue to his modest ambitions. He could have gone for broke and directed "Asia" or "South America," but no — the man who made "Romeo + Juliet" safe for the multiplex and turned "Moulin Rouge!" into a 19th-century Parisian nightclubbing fantasia, merely wants to capture the entire Down Under experience in one 165-minute "Gone With the Wind"-style extravaganza. Healing his country's centuries-old racial scars is somewhere on the punch list, too.

How big is "Australia"? It may be the first movie to come with its own sequel. As is so often the case with follow-ups, sadly, part two suffers in comparison with part one. When you experience deflationary sequelitis in one sitting, the letdown's even more acute.

For all its epic claims, "Australia" unfolds over only three years, from 1939 to 1942. The first hour and a half takes place in cattle country in the Northern Territory, and for all intents and purposes it's a western. A good one, too, shot through with energy and a self-mocking camp humor that isn't too far removed from "Moulin Rouge!"

As in that film, Nicole Kidman plays an easily shocked outsider-innocent who goes native and becomes the ultimate insider. Here, she's Lady Sarah Ashley, freshly arrived from England to bring her wayward husband (a briefly seen Anton Monsted) to heel. He's raising beef and cavorting with the locals - or so she's heard - and a few solid laughs are squeezed out of Lady Ashley's prim collision with the roughnecked chaos of daily life in Darwin. No sooner has she stepped off the plane than a street brawl has strewn her lacy unmentionables across the town square. Naughty Baz!

Chief brawler is a cattle drover named . . . um . . . The Drover, who's played by Hugh Jackman. The Drover works for Lord Ashley, who immediately turns up dead, the victim of a land-hungry cattle baron (Bryan Brown) and his ruthless henchman Fletcher (David Wenham). The widow Ashley and her strapping new employee are forced to get 1,500 head of angry cow to the army ship waiting at port, hundreds of miles away.

You're right, this isn't just a western, it's 1948's "Red River," with Jackman taking the John Wayne role and Kidman filling Montgomery Clift's boots. Although Wayne never got a sexiest-man-alive topless shower scene (in slow motion, no less), and he and Clift didn't have quite the sexual chemistry of the two leads here.

The settings are vast and sometimes depressingly unconvincing, since Luhrmann augments the continent's natural wonders with too-painterly computer-generated backgrounds. (It's like he's trying to show Peter Jackson and New Zealand who has the better country.) At the same time, the director brings history down to life-size with his depiction of the relationship between the white characters and the land's original inhabitants.

As in the 2002 film "Rabbit-Proof Fence," "Australia" casts a light on the "stolen generations" - the thousands of half-caste children forcibly removed by the government to mission schools, where they were trained to be servants. The third main character (and narrator) in "Australia" is Nullah (Brandon Walters), a sharp-witted little "creamy" whose mother (Ursula Yovich) works at the Ashley ranch. As events play out, the Drover and Lady Ashley become this lost boy's surrogate parents, even as the child is drawn to his grandfather, an aboriginal shaman who has a gift for building bonfires on cliffs distantly overlooking the main action. (Grandfather is played by David Gulpilil, who long ago was a wandering boy himself in the eerie 1971 film "Walkabout.")

Luhrmann is working a tricky game: He's trying to come to terms with modern Australia's racist legacy while telling a ripping yarn while also making fun of ripping yarns - but not too much. Just to throw one more tomato in the stewpot, he introduces the 1939 classic "The Wizard of Oz" as a sort of metaphor for the country as a whole, with "Somewhere Over the Rainbow" threaded through the soundtrack and a visit with the movie itself in a Darwin theater. That the first half of "Australia" works at all is due to Luhrmann's sizable knack for mixmaster storytelling, and to Kidman's ability to make herself look silly while holding onto our sympathies. (Catherine Martin's marvelous costumes help on both counts.) Jackman just has to stand there looking likably sexy; it's no big stretch.

Then the director's conflicted aims lead him astray. "Australia" is a very nice 90-minute movie that comes to a rousing climax, pauses for a moment while the characters clear their throats and the audience takes a bathroom break, then roars into a second story line involving the 1942 Japanese bombing of Darwin.

Suddenly, we're playing with notions of sacrifice, separation, and mother-love; Luhrmann tries to balance the epic destruction of a city with the closing of a nation's racial wounds, all the while keeping his lovers dancing around each other. The effort costs the filmmaker his natural brio; "Australia" strains to do it all, and finally all you can see is the strain.

I imagine it plays better if you're on the home team. Luhrmann has stocked his film with many beloved Australian actors - in addition to the leads, Brown, Wenham, and Gulpilil, you can spy Jack Thompson ("Breaker Morant") as a drunk, Barry Otto ("Bliss") as an official, and Bruce Spence (the gangly gyro pilot in "The Road Warrior") as a priest. There's a lot of "Waltzing Matilda" in the score (as well as Gorecki, "Oz," and, in one strange scene involving a Chinese cook and a ukelele, what sounds an awful lot like that new Jason Mraz song).

And there are, of course, kangaroos hopping everywhere, this way and that. Yet it's typical of this remarkable, overstuffed, bi-polar drama about a land of dreams somewhere over the rainbow that the roos are terribly cute - and taste even better roasted.

Ty Burr can be reached at tburr@globe.com. For more on movies, go to boston.com/movienation.