As a film critic, one is usually moved to immediate expression when a great film comes down the pike -- its ideas spur one's own, the words tumble forth in not-always-orderly fashion, the urge to share an experience sometimes outpacing the ability to parse it. Yet sometimes baldly extraordinary films thwart our initial attempts to write about them, and such has been the case with me and Andrei Zvyagintsev's "Leviathan" -- a classically robust, not inordinately complicated melodrama that nonetheless seems to be about something different every time I sit down to tackle it.

It's been a week since I saw it at Cannes, and "Leviathan" hasn't yet settled in my mind or heart; rather, it continues to unsettle, in ways both exciting and elusive. It's a film, like a rich novel, from which you might wish to re-read extracts while only halfway through; it's certainly the first film I wished I could pause while I brushed up on the Book of Job. It is, obviously enough, quite something.

On a remote stretch of Russian coastline, the yawning skeleton of a colossal sea creature rusts on the shore, defeated but still implacable, a paradoxically hopeful harbinger of doom. Even the most indomitable organisms, it reminds us, are fallible. This  resilient fence of bones is the most teasing symbol in a film of many: It may be a beached whale, but Zvyagintsev works in a vein of mythic realism that allows us to presume more majestic possibilities. Perhaps this is indeed the final resting place of the eponymous Old Testament monster -- of Satan himself -- drawn out with a hook, his tongue tied down with a cord.  

Whatever it is, Zvyagintsev suggests with some measure of wry despair, it no longer exists in a godly universe: defeating Leviathan is one thing, but defeating the many-headed monster of the contemporary Russian government is quite another. Our Job figure is Kolya (Alexei Serebryakov), a modest mechanic and family man who appears to live, quite literally, at the end of the world: the ramshackle seaside pad he shares with his son Roma (Sergey Pokhadaev) and second wife Lilia (Elena Lyadova) stands isolated before an unfettered horizon. (Russian cinema is thick with such exquisitely devastated landscapes: one half-expects the Arctic exiles of "How I Ended This Summer" to come stalking into the frame at any given moment.)

If it seems an improbably vast domain for one humble man, the powers that be agree. We meet Kolya in the bleak concluding stages of a vicious land battle with the authorities; craven mayor Vadim (Roman Madyanov) wants Kolya's piece, and isn't above any scheme of tactical framing or brute, bullying force in order to drive the family off it. Kolya hires himself a slick Moscow lawyer (Vladimir Vdovitchenkov) to help him stand his ground, but he's fighting something bigger than city hall here: as the arrangement goes horribly awry, despite the makings of an incendiary underdog case, it would appear that his downfall is fated by more cosmic arbiters than petty bureaucrats. Job is restored by God to health and prosperity; the common Russian man is granted no such grace.

This is, like Zvyagintsev's crystalline 2011 film "Elena," a moral-free fable -- one in which venality trumps all, and life either carries on regardless or ends with ceremony. The filmmaker's critics might accuse him of being an especially poetic expounder of "shit happens" doctrine, but he's a far more generous, and more ambiguous, storyteller than that. Co-written with Oleg Negin, his grand, non-linear screenplay (a heartily deserving prize-winner at Cannes) unexpectedly dovetails key revelations and withholds others, holding aloft crucial questions of culpability and consequence.

How we choose to answer them varies the film's ratio of personal to institutional corruption. You'd have to be perversely blind not to see the furious sideswipes Zvyagintsev is making here at Vladimir Putin's self-serving, socially destructive regime, as well as the defiantly un-Christian covetousness of the Russian Orthodox Church. The film's political satire can even be as bluntly literal as an uproarious scene that sees the embittered Kolya and his chums using framed portraits of stern Russian politicos for drunken target practice.

Yet the film's characters are equally undone by individual, intimate failings: a fragile, shivering anatomy of a marriage is suspended between the film's larger war between man and state. From certain angles, "Leviathan" might seem a rallying cry on behalf of The People, but from several others, it appears to take a more omnipotent, dispassionate stance: Kolya is a raggedly put-upon figure, but never a wholly sympathetic one. Amid the film's inexorable pile-up of tragedy, it's telling that its most emotionally cathartic scene features no human presence at all: merely the phantom of family life, as a bulldozer devours the domestic debris of a well-worn kitchen in one stunning wide shot. If humane nihilism is a valid concept, Zvyagintsev has it pretty well locked down.

"Leviathan's" ideas may imply a film of granitic consistency, but as imposing as it is, it's never impermeable: there's a positively thriller-like urgency to its fatalism, and ribald comedy that cuts right through its dourest thematic impulses. Zvyagintsev has gallows humor to rival Dostoyevsky at his warmest, or the Coen Brothers at their most cutting: even a crushing legal sentence is rendered hysterical by the toneless, automaton-like speed-reading of the court clerk. (No mini-characterization goes to waste in this sparse contemporary dystopia.) It's a film by turn as cruelly bare as that haunting, sprawling beached skeleton, and as mammoth and muscular as the physical body that once contained it -- its images and implications in rapid motion and rewardingly hard to capture, by hook, by crook or otherwise.

"Leviathan" will be released in the US by Sony Pictures Classics.