One of the most eye-catching titles at this year's Dubai International Film Festival is undoubtedly Death Metal Angola, a documentary looking at the metal scene in the West African country that, until a decade ago, was engaged in a brutal civil war. But were it not for a chance meeting in a coffee shop, it could well have been an entirely different - and probably less exciting-sounding - story.
Commissioned to do a film about immigration, the director Jeremy Xido had come across a railway line being constructed by Chinese workers running through Huambo in the centre of Angola, one of the cities most ravaged by the conflict.
"There's only one cafe in Huambo where you can get a decent cup of coffee," he explains. "Everyone interested in coffee is there: expats, military guys, Lebanese businessmen, people from all over the place."
Sitting there one morning, Xido got chatting to a young local guy in dreadlocks who told him that he was a musician. "He said he played death metal, and I just thought: 'I have to hear this.'"
So later that evening, he was invited by his new friend - Wilker Flores - to listen to him play at a place called the orphanage. As it turns out, it was an actual orphanage (Xido says he thought at first it was the name of a club) being run by Flores' partner, Sonia Ferreira.
"It was in this really poor neighbourhood with no electricity, and there's Wilker with an amplifier and guitar and stolen electricity from this wire. We lit him with the headlights from an SUV and he proceeded to play this impromptu death metal concert in the middle of an orphanage with kids running around. It was the most amazing thing I've ever seen."
And when Flores and Ferreira explained that they were going to organise the country's first metal concert, Death Metal Angola was born.
Over about six weeks of filming, mainly in Huambu but also around the capital, Luanda, by the coast, and Benguela farther south, Xido spoke to numerous musicians involved in the underground yet emerging Angolan death metal, thrash metal and melodic death-core scene.
What's the explanation for this unusual phenomenon? And why, as the film claims, is the "hardest hardcore Angolan hardcore"?
Xido says there are links with Portugal, Angola's former colonial ruler and a country with a strong metal fan base. "During the war, a lot of the young guys - if they had the opportunity - would go to Portugal to study to get away from armed service, and they were often exposed to contemporary rock."
There are local links, too. "Wilker says that rock is actually African in its roots, and says that a lot of the rhythms you'll find in the countryside are the rhythms you'll find in death metal."
But there are also connections to the conflict, with many of the kids having grown up either during the war or immediately after. "I think a lot of it has to do with looking back at the war and the sort of unfilled promises of post-war," says Xido, who adds that the lyrics have very political messages and those involved are highly intellectual.
"A lot of these guys are working in banks or doing IT. There's a young guy who is considered to have the best metal growl. He wanted to come to Dubai, but is studying electronics and has exams."
As shown in the film, the concert that Flores and Ferreira organised last year goes ahead and more have been put on since. Through the film - which is receiving its world premiere in Dubai this evening - international acts such as Rammstein have also begun to notice the musicians.
And as for Xido, making the film has opened his ears to metal, which he says was not what he listened to growing up. "Because of these guys I started listening to Pantera and Sepultura and I really got into it. Metal on headphones in New York is fantastic. I love the way they like it in Angola, where it's a huge expression of joy."
But what about the other film, the one about immigration and the railway? "It's still in production," Xido says.
Death Metal Angola is screening tonight at 6.15pm at Mall of the Emirates, Vox Cinemas 7 and on Saturday at Vox Cinemas 8 at noon. Xido, Flores and Ferreira are in Dubai with the film