At the centre of this story, a corpse lies in a dense patch of the Lantana weeds that plague Australian land. The body is lost, prickled by unruly pieces of nature, refusing to be found. The living characters are just as engulfed; we can see thorns surrounding the dead body, and we can sense them in every waking moment of everyone else.

Lantana, which blindsided audiences at last year's Sydney, Toronto and Telluride film festivals, is an astoundingly absorbing surprise of a movie, charged with emotion and force. It makes thoughts and emotional webs run wild in our heads, and leaves us unsure of how to describe them, simply by focusing on the complexity of people. We go through life without road maps, we become adults before we can even comprehend the idea, and we end up under the weight of our problems without even feeling suited to them. The film knows that, and gets operatic passion out of things that happen somewhere or other every day.

The shot of the dead body opens the picture; it is not explained until far into the second act, but it strikes us hard and sets a tone of sadness and enigma. We meet characters that sit in motel rooms with their illicit partners, stressed about what they're doing; or talk to their therapists, sit alone, row, wonder about their loved ones. We meet people, and hear so much of their thoughts that they start to invade our minds: Anthony LaPaglia plays a cop having an affair; he's racked by troubles on the job and in marriage. His wife (Kerry Armstrong) knows something is up, and comes close to devastation when the simple realisation hits that her husband isn't sharing a bit of himself. LaPaglia's sexual partner (Rachael Blake) has her own problems; her neighbours, who have until now been good friends, are starting to mistrust her, and she doesn't know where she stands with her ex-husband (Russell Dykstra). Those neighbours, played by Vince Colosimo and Daniela Farinacci, are struggling to make ends meet. Barbara Hershey and Geoffrey Rush are a doctor couple whose marriage is so static and uncommunicative that it cannot be described as held together; the partners have simply been frozen together by the loss of their daughter.

A disappearance occurs. LaPaglia has to investigate it, and indeed all of the above are somehow involved. The people are connected in ways not all of them realise, but as with Monster's Ball, another great piece of fiction from this year, Lantana feels no need to underline, stylise or apologise for its coincidences. The particulars of the connections and the mystery plot are not that important anyway; the set-up and the case serve as lightning rods to bring some of the characters together and face all of them with challenges.

It's hard to explain. There are plain phrases spoken, such as, "Have you ever been unfaithful to your wife?" and "Sometimes I want to cry, sure, but you just don't, do you?" The words seem important in context, because the first hour of the film has studied its subjects intensely, letting their values and feelings seep into our minds. We're thinking about these characters urgently, and decisions, word choices and confrontations take on precious significance. The murder is never solved in any conventional way, but we do find out what led the eventual victim into that situation, and this is what's important to us, because it involves character choices, human mistakes and the feelings of strangers as they collide in the night.

The actors are infused with thoughts and inner workings, and as the camera studies them, caked under the unmistakable Australian sun, we absorb everything we need to know. LaPaglia is angry, intense, tortured. Rush stands bitter and austere, as if he wants to feel disgust at something but hardly has the time or strength. Hershey is lost; she plays a thinker who doesn't know where her life has arrived or is going, and the frustration is robbing her of the capability to stand and move. Armstrong, Blake, Colosimo and Farinacci play people in vital domestic situations, fighting their way through life by refusing to let heartbreak collapse them.

Lantana  was directed by Ray Lawrence, whose last and only former feature film was the controversial Bliss (1985). It is a tremendous achievement, made with command and bravery; the events onscreen ring of personal history and experience, and it is hard to believe that a filmmaker so unfamiliar with full-length projects managed to pull it off. This piece is a question of convincing us of detailed characters despite obvious contrivances, then delving into personal dilemmas, showing reactions to unexpected situations and seeing how it all plays out. It ends up quite unreasonably thrilling

(Review also posted at http://www.ukcritic.com)

Released by Lions Gate Films and rated "R" for language and sexuality.