Image copyright Gabor Kotschy / A24

Think about a horror movie and you might imagine dark basements, attics and other badly lit places you'd probably rather stay out of.

But how about a Swedish festival in the middle of summer where the sun barely goes down? That's the setting for Midsommar, the second film from director Ari Aster.

He's the man behind Hereditary, which last year managed to please critics (89% on Rotten Tomatoes) and terrify horror fans. That was his first full-length film.

And early reviews of Midsommar seem to suggest he's got a second scary success on his hands.

But after decades of horror movies, it's not easy to scare today's film fans. After all, they've jumped at every shock and squirmed in their seats at every gruesome kill - this is 2019 after all.

Ari seems to be doing something right in his work. So we asked him: how do you make a modern horror film scary?

Here are his tips:

1. Ease up on the jump-scares

Cats leaping out of a cupboard? You won't find any of that in Ari's movies - there aren't any jump-scares to be found in Midsommar.

"There is a trend in the genre of essentially stacking jolts on top of jolts and prioritising that over story and character," he tells Radio 1 Newsbeat.

"Jump-scares agitate me and I don't particularly enjoy them."

Image copyright Csaba Aknay Image caption This Swedish community couldn't mean any harm, could they?

But if you've seen Hereditary, you'll know there are unexpected scares that make you jump - he just believes they earned their place in the film.

"I had a rule for myself on Hereditary which was, if this is a moment that is asking for a jolt like that - then I'll give myself to it. But for the most part I'll avoid jump-scares and I certainly won't look for them."

Image copyright A24 Image caption Ari's previous film Hereditary starred Toni Collette as the mum of a family dealing with supernatural forces

For Ari, what's important is how the viewer feels when they leave the cinema, rather than raising their heart rate during the film.

"When I was a kid, the horror films that really struck me were the films that presented me with images that didn't leave me for a while or moods that I couldn't walk right out of," he says.

2. Be patient

Midsommar is two hours and 20 minutes long. In one early scene Florence Pugh (Dani) has a long phone conversation with her bored boyfriend (Christian), and the camera remains on her face for the whole thing.

It's not a film that's in a hurry to get to the gore.

"I know that as a viewer myself, I'm never really taken anywhere by a film unless I'm able to fall into it," says Ari.

"If I haven't attached myself to the characters - or to at least one of the characters - I'm completely detached from the experience and don't really care what happens to anybody.

"I do believe in patience and I do believe in establishing a very solid foundation that you can build on."

Image copyright GABOR KOTSCHY Image caption Dani (Florence Pugh) takes a trip with boyfriend Christian (Jack Reynor) but can't escape her own grief

Midsommar's most unique aspect, the relentless sunlight, was a key part of creating that foundation, despite presenting a "huge challenge" for Ari and his crew.

"Making a horror film in broad daylight, I kind-of gave up on the idea of quote-unquote scaring people from the very beginning," he says.

"The goal was again to just create a world that people could live in and stand in and lose themselves in."

But horror fans don't need to worry - the film packs enough shocking moments to keep even the most hardened viewers happy.

3. Tap into everyday horror

Most of Midsommar is set in a remote Swedish community, but the film opens with a family tragedy for Dani - one which follows her all the way to Europe.

The grief in Midsommar - and Hereditary - is something Ari describes as existing "for us even if only as a low hum under everything else, from day to day, all through our lives."

"I see both films as being existential horror films that are contending with fears that don't have any immediate remedy.

"Fear of death, fear of losing the people closest to us. The fear that we can never really know the people closest to us.

"I'd say the film is touching on all of that stuff - and at the same time, the movie is a break-up movie."

Image copyright Merie Weismiller Wallace Image caption Christian's friends Josh (William Jackson Harper) and Mark (Will Poulter) are also out to enjoy the Swedish hospitality

It was Ari's own grief - a really bad breakup in this case - that prompted him to make Midsommar and he hopes people who've been through something similar will understand his intentions in making the film.

"My goal - and I was saying this to my producer and my cinematographer before we even made the film - if the film ends up working, I hope that people go to when a relationship ends and they're going through a break-up," he says.

"I'd say that would be my fantasy for how this movie might live."

And that's definitely something you might want to think about when you've seen how Midsommar ends.

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