Netflix bought the first great horror movie of the year at Sundance - here's why you need to see it

The midnight section at the Sundance Film Festival can be hit-or-miss, but when the program is done right, it includes some of the best movies at the festival.

The section has a gem this year from a first-time Iranian filmmaker who has looked back on his memories growing up through the Iran-Iraq War in 1980s Tehran to make a chilling horror, "Under the Shadow."

Horror movies have been used perfectly over the decades to comment on topical issues within the US (from civil rights in 1968's "Night of the Living Dead" to the big-brother-is-watching angle of 1988's "They Live"). But only recently have filmmakers of Middle Eastern descent begun to tell such stories on an international stage in a significant way.

"Under the Shadow" director Babak Anvari will quickly be compared to Iranian-American filmmaker Ana Lily Amirpour, as she also used the horror genre to explore living in Iran with her acclaimed 2014 film "A Girl Walks Home Alone." But both stories are different in tone and style, with "Alone" shot in black-and-white and focused more on female isolation, while "Under the Shadow" has slick camera work and tackles a family dynamic.

"This is a personal story about what I remember as a child and what my family went through, other Iranians went through [during the Iran-Iraq War]," Anvari told Business Insider at Sundance. "I used all those memories and put a horror twist on it."

The film focuses on Shideh (Narges Rashidi) and her daughter Dorsa (Avin Manshadi), who have a hot-and-cold relationship that only gets more challenged when Shideh's husband is sent off to serve in the Iran-Iraq War while Iraqi air raids rain down on their apartment complex.

The terror of that setting is elevated when Dorsa tells her mother that an invisible figure, or as they call it djinn (a spirit that steals those they want to posses), keeps entering their place and has stolen her favorite doll.

The tension and scares only increase from there, as neighbors begin to leave because of the bombings, Dorsa becomes ill, and Shideh realizes that what Dorsa tells her may be true.

"From day one I felt like this was a great setting for a horror," Anvari said. "Tehran at that time was very intense and dark because of the war."

Anvari, who lives in London now and hasn't been back to Iran in close to five years, remembers as a child staying up late at night to watch VHS tapes of his favorite horror movies (Anvari points out that at that time VCRs were illegal to own).

"I was influenced by horrors, but they freaked me out," he said. "My parents realized what I was doing and banned me from watching horrors."

But he was already hooked. Writing the "Under the Shadow" script on spec, he found the support of producers Emily Leo and Oliver Roskill, who were able to put together financing through their own production deal and a grant from the Dohan Film Institute to shoot the film in Jordan last year.

Though there are some computer-generated scares, most of the things that will frighten you are just good old-fashioned tricks that were used by the masters like Dario Argento ("Suspiria") and Wes Craven ("Scream").

It's been a long time since I've heard actual screams in a movie theater, and they could be heard numerous times throughout the screening of "Under the Shadow" I attended.

It certainly got buyers' attention. Netflix bought worldwide streaming rights to the movie the first day of the festival. Then two days later, Vertical Entertainment and XYZ Films announced that they were teaming up to give the film a theatrical/VOD day-and-date release.

But Anvari is realistic about where the film can be released and where it can't - like in Iran.

"Someone will buy it off the street," he said, referring to the bootleg-movie market in Iran. "It would be great to show it there, I don't feel I offend anyone, but my guess is it will be a bootleg version they see."