This summer’s scariest film is all the more disturbing for taking place in brilliant sunshine – and, in that, it’s part of a subversive horror tradition, writes David Opie.

As children, we come to believe that darkness is our enemy and the morning light, when it finally arrives, is our friend. For most of us, this concept continues to perpetuate into adulthood thanks in large part to the movie business. Over the past hundred years of horror, monsters – whether they be vampires, demons or ghouls – have invariably hidden in the shadows – and even if these creatures don’t keep you awake at night, Freddy Krueger will still come for you in your dreams. 

But what happens if that fear is misplaced – and the boogeyman strikes when the sun’s still high? The results have the potential to be even more terrifying.

This summer, director Ari Aster is thrusting horror fans out into the glaring light of ceaseless sunshine for his already much-discussed Midsommar. Set during the summer solstice, Aster’s follow-up to his equally terrifying debut Hereditary features a group of American twenty-somethings who visit a pagan festival in Sweden and become entangled in its dangerous rituals.

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Its terrors are compounded by its setting amid the blinding midnight sun that engulfs much of Scandinavia and other Arctic regions in June: by shooting Midsommar’s scares almost exclusively in the daytime, Aster subverts the horror paradigm, invading the ‘safe space’ that light usually provides. 

The streaming service Shudder has added a ‘Sun Scorched’ section to their growing roster of horror classics

Scary movies tend to make an unspoken promise with the audience, which suggests that they have nothing to fear as long as the camera stays in the light. Aster deliberately breaks that promise in Midsommar – and he’s not the only filmmaker to have done so. Contrary to popular belief, some of the scariest scenes ever committed to film play around with this notion of ‘daylight horror’. Recently, the streaming service Shudder even added a ‘Sun Scorched’ section to their growing roster of horror classics. But what is particular about sunlit scares that can make them so effective?

“We tend to be much less paranoid” when scary movies switch to the daytime, making us “all the more vulnerable,” notes Dr Bernice Murphy from Trinity College Dublin, who adds that “if you're alone in a dark old house you can always find at least some sanctuary in the comforting glare of a candle or an electric light, but no such escape is possible when horror strikes in the brightness of day time.”

What’s more, when bad things happen in daylight, there's simply “an even more profound sense of ‘wrongness’”, she says. For example, many of the scariest scenes in John Carpenter’s Halloween “take place quite early on in the film as [Michael Myers] lurks amidst the quiet hedgerows and streets of Midwestern suburbia, unnoticed by everyone but [the film’s] ‘final girl’ Laurie.” 

Blue-sky killing

Jonathan Barkan, horror expert and editor-in-chief of website Dread Central, tells BBC Culture he’s full of praise for directors who “are willing to bring their terrors into the light” – chief among them Tobe Hooper, whose seminal 1970s exploitation flick The Texas Chain Saw Massacre is a classic of the subgenre. For many fans, Sally’s nightmarish escape at dawn at the film’s climax is its most enduring moment, but for Barkan, it’s an earlier scene, in fact, that represents ‘daylight horror’ at its most scorching.

Right after her boyfriend is slain by Leatherface, the ill-fated Pam walks towards the dreaded Sawyer house in search of him. “If the scene is taken out of context, it's actually quite beautiful,” says Barkan. “A pretty woman with lovely skin walks towards a picturesque house, the camera low but capturing the bright blue sky with puffball clouds lazily suspended in the air.” However, given what we know about the dangers that await Pam inside the house, it’s not long before “the beauty of bright daylight [becomes] a blaze of impending danger,” reminding us that monsters can strike in even the most idyllic and gorgeously lit settings.

The list of ‘daylight horror’ films is an eclectic one, ranging from Deliverance, in which four men’s picturesque outward bound trip is disturbed by sadistic locals, to notorious video nasty I Spit on Your Grave and of course, Jaws, where the beachgoers of Amity are terrorised by the iconic great white shark. And then there are those films which contain particularly terrifying scenes that are accentuated by being well lit: think of the moment in Jack Clayton’s The Innocents, where the ghost of the dead governess Miss Jessel appears by the lake, or in David Fincher’s Zodiac, when a couple are set upon by the Zodiac killer while enjoying a picnic.

But while horror auteurs have played around with the notion of sunlit scares for decades, Midsommar director Ari Aster is the first to take daylight horror to its logical extreme by crafting frights fed by 24/7 sunshine. The most notable films to previously take place under the Arctic’s ‘midnight sun’ are the Norwegian thriller Insomnia and its US remake, which both centred on a detective trying to catch a killer while becoming increasingly frayed by the piercing permanent daylight.

Summertime scares

But Aster has creepier things on his mind than mere disorientation. Indeed, with its strange summer rituals and dreamlike, psychedelic ambience, his film has a clearer “daylight horror”  forebear: 1973’s  The Wicker Man.  Although Robin Hardy’s film lets the night creep in a tad more than Midsommar, both films make something sinister of summertime, and reserve their scariest moments for daytime.

Summer solstice legend says that on this special night, seals turn into humans and cows gain the ability to talk

Judging by its folklore, after all, summer is far from a benign season. Summer solstice legend says that on this special night when the boundaries between worlds thin, seals turn into humans and cows gain the ability to talk – at least, according to Icelandic tradition – while centuries ago, it was a time when Vikings supposedly hung corpses from trees as a sacrificial gift to the gods. And in real life, it’s easy to see how the relentless sunshine of days that seem to last forever can unsettle people.

Indeed, aside from the obvious damage caused to our skin by UVA rays, psychologists have discovered that sunlight can also exacerbate certain symptoms of mental illness – and no, we’re not just talking about those who suffer from heliophobia, which is a fear of the sun itself.

In a paper last year, Korean psychologists Chul-Hyun Cho and Heon-Jeong Lee investigated what has been termed ‘spring mania’ phenomenon: the fact that statistics show that people diagnosed with mood disorders report more manic episodes once the sun has returned in spring. In this same report, it’s mentioned that many studies have shown suicide rates peaking around that time too, possibly due to a misalignment between the internal circadian rhythms which manage our sleep and the 24 hour behavioural cycles that society imposes on us.

Science writer Jessa Gamble tells me that while living under the midnight sun can be a positive experience for some who live in Arctic environments, for many others it is the opposite: “It has always interested me that, while there is a lot of attention paid to seasonal depression in the winter, the little-known flip-side is that long summer days can often trigger mania.” But it’s something Aster is clearly aware of. His film isn’t just subverting convention – it’s playing off the anxiety that can be precipitated by what might be termed ‘excessive daylight’.

Perhaps the reason there isn’t more ‘daylight horror’ is that it makes the terror feel too real.

So why has it taken so long for someone like Aster to tackle this phenomenon directly in horror? Given how much potential there is to find fear in the sunshine, it’s surprising that more scary films haven’t pushed back the shadows to exploit daylight horror in this way. Perhaps the reason is that it simply makes the terror feel too real.

After all, while fairytale monsters hide under the bed and wait in the darkness, real-life horrors far scarier than any mere ghoul often occur, indiscriminately, in the hours before nightfall. As Phil Nobile Jr, editor-in-chief of horror magazine, Fangoria, says, “horror in broad daylight is so effective because it’s infinitely more relatable… it’s where you’ve seen most of your personal trauma.” From funerals to school shootings and even terrorist attacks like 9/11,  a “bright, banal lighting scheme [has been the backdrop to] pretty much every real-life horror you or I have endured,” he says. “It’s called ‘the harsh light of day’ for a reason.”

Midsommar is released today in the US, UK, Canada and Ireland

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