One of the joys of the beguiling 2011 documentary Dreams of a Life was the resultant anticipation concerning the assured hand of its director, Carol Morley. Weaving together interviews with gauzy recreations, Morley’s investigation into the fascinating story of Joyce Carol Vincent – dead in her North London bedsit for three years before being discovered – was a singular treat. The mystery and sadness of Morley’s film lingered a long time in the memory, her evocation of a pulsing, anonymous and forgotten life an impressive breakthrough success.

So it is with a keen sense of disappointment that her new feature The Falling fails so thoroughly to convince. And not for lack of trying, either. Clearly sprung from a fertile mind, Morley’s story of mass hysteria in a well-to-do girls’ school seems constantly poised to captivate and bewitch, but the spell never extends beyond the screen, even if those under it are admirably game.

Lydia (Maisie Williams) and Abbie (Florence Pugh) are best friends enduring the matronly doctrine of their buttoned up school and its fusty teachers. After a tragedy resounds through the lives of the students, a strange fainting epidemic weaves its way through the corridors of the school. It’s 1969 but the setting could be 1949. Anything resembling the cultural tumult of the 1960s seems worlds away. Indeed, some of the film’s less fevered elements include TV footage of the moon landing and pop music heard from the radio – transmissions from an elsewhere barely perceived in the insulated world these people inhabit. It’s a nice bit of cultural context, barely perceptible amid the somewhat cringeworthy chaos that takes over the school, and eventually the entire film as Morley whips between the students’ mysterious illness, undercooked domestic drama at Lydia’s home and some quasi-mystical overtones bolstered by Agnès Godard’s admittedly stunning cinematography.

The shadow of Picnic at Hanging Rock looms large over The Falling, and the story, characters and even setting bear such similarities that it’s hard not to compare one with the other. The haunting and unresolved nature of Peter Weir’s classic 1975 mystery is similarly ambiguous in Morley’s vision of fainting and sensuous bouts of near-orgasmic rapture, but whereas the mood of Weir’s feverish girls’ nightmare was ghostly by nature of a disappearance, The Falling displays its mystery front and centre. Morley’s cast of young actors prove more than willing to play possessed, but soon all the fainting and fits escalate to almost comical effect, which left me more befuddled than bewitched. References to the occult and lay-lines are scattered into the mix by Lydia’s sinister older brother Kenneth (Joe Cole), but it adds little to an unfocused story that strives for heady intoxication and never quite gets there. Part of this is due to the amount of time devoted to Lydia’s fractured home life and the volcanic attitude she displays towards her near-catatonic mother. If it felt like this and Lydia’s sudden fainting spells had any relationship beyond a pat cry for help, the kitchen sink stuff might not seem so jarring amidst the faintly psychedelic ecstasy taking over the school’s assembly hall.

Praise should be singled out for Maisie Williams and Florence Pugh as Lydia and Abbie. They share a tangible chemistry and add some very welcome colour to a friendship that might otherwise have been too easy to characterise as a boilerplate tomboy/nymphet duo. Lydia’s mix of frustration and devotion to Abbie’s carefree daydreaming is nicely captured, but even this minor virtue is eventually snuffed out by Morley in search of more nebulous threads.

The maddening impression that The Falling might have been great never leaves. It might have been a dreamlike paean to sisterhood and burgeoning sexuality in a cloistered world, were some of the girls’ exchanges not delivered like juiced-up Enid Blyton. It might have been a disturbing look at the contradicting teenage pressures of conformity and individualism if the fainting spells weren’t supplanted by the most overwrought contortions this side of Woodstock. You wonder if they weren’t merely trying to turn on and tune in with their peers on the other side of the Atlantic. And it might have been an enjoyably hot mess if any of the fainting, the hysteria, the occultism, the growing pains or the domestic drama hung together. The Falling is a film in thrall to its subjects and subject matter, overwhelmed by its ideas, influences and imagination. For the viewer, it’s something akin to showing up at the wrap party, Kool-Aid already drank dry by cast and crew.