This supernatural shocker from Norway delivers Carrie-like chills, but its half-serious dabbling in the religion-versus-science conflict is ultimately unsatisfying. Best to appreciate a skillfully made, emotionally gripping movie for its entertainment value alone. Director and co-writer (with Eskil Vogt) Joachim Trier goes on my short-list for terror.

The pre-credit teaser shows Thelma, age 6, walking across a frozen lake with her father, played by Henrik Rafaelsen, who holds a hunting rifle. Thelma watches as he sets his sights on a deer. What happens next is both disturbing and tantalizing, to say the least. The film returns to those childhood scenes later, for a major shock.

The story shifts to the teenage Thelma, played by Elli Harboe, who is realizing her dream of studying biology at a modern university. But we see that she is troubled by more than homesickness. She seems to freeze with terror at any social contact, and is willfully isolated. In phone conversations with her father, he warns her of losing faith among the non-believers, of alcohol and of sinful thoughts.

But, instead of going into familiar, coming-of-age territory, the film veers into the supernatural. While studying at the school library one day, she experiences an epilepsy-like seizure from which she loses consciousness. Initial tests are inconclusive; there is no history of epilepsy in her family. Thelma is then approached by Anja, a slender, beautiful girl student, played by Kaya Wilkins, who witnessed the seizure. Their friendship soon develops into attraction, for which the inexperienced Thelma is totally unprepared. Soon she is drinking alcohol with Anja, and their kissing becomes more passionate. Deeply ashamed, she prays for God to drive the impure thoughts from her.

Further testing reveals that she does not have epilepsy, but is diagnosed with psychogenic nonepileptic seizures. In Thelma’s case, however, there is evidence of telekinetic powers that accompany the seizures. She also discovers that her grandmother, contrary to what her parents have told her, is still alive and is confined to a sanitarium for the mentally ill. She visits her there, but the woman is in a psychotic trance, and fails to recognize her. Thelma is told by a staff member that the woman believes that her own thoughts caused her husband to disappear, without a trace, many years before.

Thelma is unable to withstand the combined pressures of this frightful news, her feelings for Anja and studying for her exams; she returns home to her parents. But they confess that they know the real reason for her distress, that it stems from dark secrets from her childhood. We learn of the fate of Thelma’s infant brother when she was a child, and why her mother is confined to a wheelchair. Torn by guilt, Thelma’s father is forced to make a terrible choice, one that he had avoided for many years, leading to the film’s violent climax.

Trier knows the tropes of the chiller film very well. The film is languidly paced, with dark, creepy music until he slams a stunning, sometimes grisly surprise at you. The use of flashing lights in Thelma’s MRI exam is another unsettling effect, with an opening credits warning for those prone to seizures from it. The performers are perfectly cast and directed to lull the audience into a slow, unsuspecting absorption. Elli Harboe, as the teenage Thelma, is enormously sympathetic, projecting fragility and innocence. Also outstanding is Henrik Rafaelsen as her father. We see a tortured man of decency, with an uncanny gentleness that is ultimately frightening.

A few minor quibbles: birds crashing into windows and snakes as symbols for forbidden sex are both tired film cliches by now; retire them. Also, the seizure in the swimming pool doesn’t work; it’s too obvious a set-up to scare. But there is a major dissatisfaction with the story as well. Trier never comes out with his own perspective on Thelma’s powers. Is it some human ability that has thus far escaped scientific detection? Or is it a divine gift, the performance of God’s will? Trier leaves the question unexplored.

You can’t fully blame him for that. Altered States, for instance, came a cropper by promising more than it delivered. Paddy Chayefsky and Ken Russell tantalized us with an often thrilling, mind-blowing treatment of anthropology, only to founder in the attempt to depict a vague pseudo-Jungian theory in cinematic terms. The climax was memorably dumb, and you could see why Chayefsky disowned the final film. But Elmore Leonard’s cop-out in his novel Touch, in which a modern-day Jesus has unexplained healing powers, is no better. It may be that Trier wanted to avoid the usual, “Stephen King” take on movie telekinesis: it’s Satan, stupid! Instead, Trier correctly infers that the more believable he makes telekinesis, the more frightening it is. Trouble is, he made the condition so realistic that I wanted something that no other film ever gave: a conclusive scientific or theological explanation for  it.