Lars von Trier’s latest film boasts not just four chapters but a prologue and epilogue, the latter two accompanied by Almirena’s ravishing second-act aria “Lascia ch’io pianga” from Handel’s 1711 opera “Rinaldo.” In it, she bemoans her fate as a captive, separated from the man she loves; “Let me weep over my cruel fate, and sigh for freedom,” she sings. “May my grief mercifully break these chains of anguish.”

The words encapsulate the theme of “Antichrist,” which in its three chapters focuses on a mother’s depression over the death of her child and her therapist-husband’s doomed attempt to see her through it. But though it has moments of extraordinary visual power, unlike the aria it’s anything but beautiful. Even at Cannes, where audiences tend to be adventurous, the picture was greeted with catcalls, reviled as misogynist and repugnant; it’s clear that the bad-boy provocateur of contemporary cinema was out to shock, and he succeeds with scenes of violence all the more awful because they have none of the usual horror-movie camp—including a shot of genital mutilation so explicit as to be genuinely disgusting.

“Antichrist” opens with a sequence that’s oddly reminiscent of one of the tropes of slasher flicks—the inevitably bad result of teens having sex. In the prologue, shot in luminous black-and-white, a toddler climbs from his crib and falls out a high window onto a snow-covered street while his parents, identified only as He (Willem Dafoe) and She (Charlotte Gainsbourg), engage in strenuous sex in the bathroom, oblivious to the tragedy unfolding in their apartment.

In the first chapter—“Grief”—She leaves the hospital in her husband’s care, and he tries to lead her through her understandable trauma to some kind of mental equilibrium again. After much subdued recrimination and several angry episodes, He decides to push her to overcome her block by taking her to the place she says she most fears, the remote forest where their cabin “Eden” is located—the place she’d stayed with her son the previous summer. In this rustic section, called “Pain,” she seems to improve, but the sad reality is enunciated by a bloodily brutalized fox that suddenly tells the man, “Chaos Reigns”—the chapter’s subtitle.

That moves us into part three, “Despair,” subtitled “Cynocide.” Here She flies into a rage against her husband, eventually venting her fury in a manner that recalls “The Toolbox Murders” taken up a notch. Then, in the final chapter, “The Three Beggars,” represented by a deer, a fox and a crow (a celestial constellation, as the husband informs us, that doesn’t exist), She turns on herself. And He’s left to leave the woods alone, though The Feminine, so to speak, is hardly absent.

It’s not entirely clear what von Trier intends to tell us in “Antichrist.” One message is certainly that psychology has distinct limits in dealing with grief. But that’s a pretty mundane, limited point in a picture that, despite long, prosaic passages and episodes of grisly realism, also strives for a hallucinatory quality. The larger meaning seems connected with the otherwise inexplicable title, which suggests that the picture is intended as a sort of anti-Genesis, in which Eden becomes the place that reveals the depths of the innate evil of nature and humankind, too, where man and woman, far from becoming one, are definitively separated, with the woman being the instigator of the split. (An accompanying thread is with man as coldly rational and woman as uncontrollably passionate, the two warring sides of the human psyche.)

But if those are the kinds of points von Trier is trying to make, he certainly does so opaquely, in a way designed to shut people out rather than drawing them in. While there a moments of great beauty in his film, he apparently feels compelled always to make them rather seedy. The gorgeous prologue, reminiscent of the style of “Zentropa,” is, for example, suddenly interrupted by an in-your-face shot of Dafoe’s bare buttocks (a portion of the anatomy that becomes almost a motif). The animal symbolism of deer, fox and crow has the feel of a fairy-tale that out-grims the Grimms but comes across as utterly arbitrary. Much of the picture’s first hour is verbose and has the feel of dull improvisation, and will certainly bore most viewers to tears. Then the final half-hour goes for the jugular in ways that are obviously designed to repel in a portrayal of the male-female divide all the more horrifying for its mixture of grotesque realism and dreamlike weirdness.

You do have to give credit to the stars, however, if only because of their willingness to hand themselves over to such degradation. Dafoe maintains his dignity even in his most wounded state, and Gainsbourg captures both the woman’s moodiness and her extravagant flights of madness. One should also mention Anthony Dod Mantle’s cinematography, which meets the director’s very different demands in the picture’s varied sections.

“Antichrist” isn’t a coherent film as much as a kind of cinematic Rorschach test, designed to elicit feelings of puzzlement, admiration and indignation, sometimes simultaneously. It’s certainly fascinating, but the fascination is of the morbid sort you might associate with a car crash. Von Trier’s film is very hard to watch, and in the end it’s doubtful that it’s worth the effort. But it has moments you won’t forget, however much you may want to.