I remember seeing Peter Weir’s Picnic at Hanging Rock on TV, probably when I was about 11 or 12. It must have been my first experience of a film that didn’t provide a proper solution to its mysteries, and my response was to be quietly devastated. Those beautiful, evanescent girls, all golden-lit and white-gowned, climbing into the penetralia of Hanging Rock like a reverse version of Edward Burne-Jones’s The Golden Stairs (of which he wrote, “I have drawn so many toes lately that when I shut my eyes I see a perfect shower of them”) — never to return. Nor to have their disappearance even explained. But that’s the thing I most love about the film now, its refusal to explain what happened, its keeping faith with the mystery. Because, Picnic at Hanging Rock isn’t so much about the disappearance of the girls and their teacher into a million-year-old maze of volcanic rock, but the devastating effect this has on those who remain.

The film starts with a vision of intensely Romantic adolescence: the girls of Appleyard College swapping poetic Valentines, then setting out, white-gloved and straw-hatted, for Hanging Rock. (They’re told that, as the day is hot, they may remove their gloves, but only after they’ve passed through the nearby town, as though the sight of so many nubile female fingers might set the working classes into a frenzy.) There, in the midst of a mid-day swooze, four girls set out to explore the rock. Everything assumes an unreal, almost ritual air. Moany Edith cries, “Where in the world are they going? Without their shoes?”, and the answer is, of course, that they aren’t going anywhere in the world, they’re going out of it, and the fact they’re not wearing shoes is like one of those odd bits of folklore about the dead, such as that their heads are on back to front, or they cast no shadows. The girls engage in a bit of dreamy philosophising:

“A surprising number of human beings are without purpose, though it is probable that they are performing some function unknown to themselves.”

and:

“Everything begins and ends at the exactly right time and place.”

Then… they disappear. There are some odd, UFO-like details that emerge, such as the fact that their teacher, Miss McCraw, was last seen without her skirt, and that the recovered girl Irma was without her corset. (The doctor who examines both Irma and moany Edith is always sure to point out that the girls, apart from a few scratches and sunstroke, are “quite intact”.) This loss of garments seems to be more about shocking the proprieties of the ultra-conventional upper-middle classes than providing any clue to what really happened to the girls.

There are three levels of reality in Picnic at Hanging Rock — or, two of reality, one of unreality. There’s the “reality” of those upper-middle classes, which mostly consists of an education in deportment and senior needlework, the attendance of overdressed garden parties, and sitting dully under the shadow of Hanging Rock, looking at nothing, feeling nothing. Faced with the incomprehensibility of mystery, this level of “reality” shakes its head and retreats behind the wings of an overstuffed chair, to read about it in a newspaper. (Squeaky Miss Lumley, who teaches at the girls’ college, finds it almost frightening that someone should do such a strange thing as sit on the stairs in the dark, so it’s no wonder she can’t face the idea that some of her charges might have disappeared altogether.) Then there’s the grounded reality of the working classes, the servants and local townspeople. Theirs is a much more human reality, all about the simple pleasures, and the simple un-romantic love of two servants in Appleyard College catching a spare moment to jump into bed together. Faced with mystery, they resort to lurid theories and melodrama — kidnappings and Jack the Ripper style murders. (Only the old gardener knows the right way to face this kind of situation: “There’s some questions got answers, and some haven’t.”) Finally, there’s the unreality of the evanescent — the adolescent girls wrapped up in their poetry and idle philosophising, evaporating in the heat of the Australian sun before they have to face the reality of their looming adult lives. (The exception to this, of course, is the scientific-minded Miss McCraw, with her “masculine intellect”. Why she disappears is a mystery about this particular mystery.)

Michael Fitzhubert (played by Dominic Guard, who also voiced Pippin in Ralph Bakshi’s Lord of the Rings), though part of the self-blinded upper classes, finds one of the girls — Irma — but only after searching obsessively enough in the outback heat that he falls into a fever. It’s as if he has to pass from reality into unreality to fetch her. (“I’d give my head to really know what happened up there,” the doctor says, after examining the concussed Irma, and it’s probably the price he’d have to pay — though it would be the loss of his rational, sane mind, not his actual head.)

The original theatrical release featured a brief, failed romance between Fitzhubert and the rescued Irma, later excised in Weir’s director’s cut. It’s a pity, because Fitzhubert’s inability to fall in love with Irma, and his continued obsession with the absent “Botticelli angel” Miranda, is all part of the devastating effect the mystery has — you get the feeling that this young man will never get over the disappearance of a girl he only ever glimpsed once, crossing a stream in a beam of sunlight, and will in fact be unable to love any real woman. She didn’t just take herself from this world, she took his soul, too.

Picnic at Hanging Rock is one of those rare films that sustains a ghostly, fantastical air without any resort to the supernatural. For me, it fits perfectly alongside films such as The Spirit of the Beehive, Hitchcock’s Vertigo, or David Lynch’s Lost Highway or Twin Peaks: Fire Walk With Me, as being set in the liminal zone between outright fantasy and interior psychology — “a Dream within a Dream”, as it says (quoting Poe) at the start of the film.

(The film Picnic at Hanging Rock was based on a novel of the same name by Joan Lindsay, who was married to the artist Daryl Lindsay, who was brother to the artist & writer Norman Lindsay, who featured in the 1994 film Sirens.)