Jonathan Glazer began his directorial career with the high-strung “Sexy Beast,” which barreled along on the energy of Ben Kingsley’s high-octane performance, but then suffered a sophomore stumble with “Birth,” a lugubrious fable that might have had something to do with reincarnation but certainly took itself much too seriously. He sinks further with this even more funereal exercise in sci-fi topoi that aims to be mysterious but merely comes off as monotonous.

The big draw of “Under the Skin” is Scarlett Johansson, who literally bears it all as an unnamed woman who’s actually an extraterrestrial creature fashioned by a motorcycle-riding handler to seduce earthly males and lead them to their destruction. The purpose of the exercise isn’t entirely clear; perhaps the men are taken as test subjects for experimentation, perhaps they’re consumed as food. The screenplay by Glazer and Walter Campbell, adapted from Michael Faber’s novel, isn’t terribly clear about the details of that or very much else.

What’s shown is that the handler, who’s apparently arrived in a spaceship we see slowly coming into view in the opening scene, begins the process by either killing a hooker or finding her dead, and taking the body to the ship, where Johansson dresses herself in the prostitute’s clothes. Cut to the streets of various Scottish cities, where she’s driving around in a van, accosting men she happens upon with innocuous requests for directions before inviting some of them for a ride and taking them to an isolated location, where she strips, invites them to do likewise, and then leads them into a sea of oily liquid into which they sink while she walks none too demurely over the surface. A sort of variety is provided by a sequence in which she introduces herself to a swimmer on a near-vacant beach, only to conk him on the noggin after he returns exhausted from a vain effort to rescue a couple that have somehow gotten swept up in the choppy waves. He’s then carted off, presumably to his soupy fate, along with an infant that’s been left wailing on the beach by the drowned couple. One has to assume it’s chucked into the goo, too—an unsavory grace note.

The woman’s attitude changes, however, when she induces a disfigured man into her van, only to let the fellow escape the ooze when he’s at point of demise. (Her handler, as it happens, will rectify her act of rebellion.) Now she goes on the run. Disoriented, she’s taken in by a kindly man for a time but ultimately falls afoul of a brutal one. It’s difficult to discern whether the point of all this is that we’re all—earthlings and aliens—alike under the skin in that we’re capable of empathy, or in that we’re capable of cruelty. Or perhaps the point is that we’re susceptible to both. In any case that’s not a terribly sophisticated message, nor a very enlightening one.

But Ward doesn’t appear to be interested in conveying anything of substance; he obviously considers himself a visual artist with dreams of being hailed as a new Kubrick or Antonioni. Even on those terms, however, his film is a grave disappointment. There are occasional striking images, but for the most part they’re little better than accidental. For most of its running-time, and especially in the exteriors, “Under the Skin” comes off as lackadaisically, even carelessly shot (the cinematographer is Daniel Landin), and even the more evocative interior moments—those set within the dank, cavernous ship with its beckoning sea, where we see the victims suspended in the liquid until they…well, I won’t ruin the effect—don’t manage to achieve the sense of wonder the makers are obviously straining for. (It doesn’t help that they’re accompanied by a throbbing electronic score, full of thuds, squeals and wails, that’s meant, one supposes, to suggest heartbeats.)

Those of us who dismiss “Under the Skin” as an exercise in pretentious vacuity will probably be seen by its enthralled advocates as philistines incapable of appreciating its poetry and soulfulness. Perhaps so, but at least we’re able to recognize such simple virtues as comprehensibility and solid construction that Glazer’s movie conspicuously lacks. This is the sort of film that should have the word “cult” stamped onto the canisters containing the reels.