Set in Zambia, the sharp satire "I Am Not A Witch" has premiered to strong reviews at the Cannes film festival.
Set in Zambia, the sharp satire "I Am Not A Witch" has premiered to strong reviews at the Cannes film festival, taking aim at the blatant sexism behind accusations that overwhelmingly target women.
White tourists are seen gawping at women detained in a "witch camp" in the movie, taking pictures of them as if they're animals at a zoo.
The supposed witches have to move around attached to giant spools of ribbon, something Nyoni invented to help the farcical nature of the accusations hit home.
"It's to stop them from flying," an official tells the tourists. "They can even fly to the UK."
For Nyoni, who was born in Zambia and raised in Wales, satire was the only way of dealing with an issue this absurd.
"What I really wanted was a way to bring the audience into something that's serious," she added.
"Humour is a great way to get people engaged and feeling for the characters."
For her first feature film the 35-year-old drew inspiration from a trip back to Zambia to visit family a few years ago, when a neighbour accused a relative of being able to turn into a snake.
"I started noticing lots and lots of witch accusations," Nyoni said, despite an official ban on such practices in Zambia.
For research she headed west to Ghana, where for decades women accused of sorcery have been sent to live in segregated camps. Grandchildren can visit, and they can go to church, but they are forced to work in the fields for local chiefs. It is, Nyoni says, "blatant" exploitation.
Nyoni spent a month at a camp, listening to women's stories.
It was a "bittersweet" experience. Most were elderly women who said they'd been banished over personal feuds -- by neighbours jealous that they were running successful businesses, for example.
There are similar stories from Tanzania to the Central African Republic. Nor is the problem unique to Africa: in India, hundreds of women are attacked every year over similar accusations and some of them murdered.
Often the real goal is financial gain -- taking over the woman's home or farm.
Nyoni recalls meeting one tribal chief explaining that witches were almost always female because "women are evil".
"This is an African version of misogyny that exists everywhere," she said.
"Wherever human beings have the ability to exploit, they do."
Hailed as "winningly original" by The Hollywood Reporter, "I Am Not A Witch" stars nine-year-old Maggie Mulubwa as Shula, an orphan who is sent to a witch camp and then turns out to have a talent for using her supposed powers for solving crimes.
Nyoni auditioned more than 900 girls for the part, but couldn't stop thinking of a little girl her husband had photographed near Samfya in the north of Zambia.
Thus began an epic hunt to find Maggie that involved the film crew sending her picture to a local tribal chief -- who then passed it on by WhatsApp until the search spanned tens of thousands of kilometres.
Eventually they tracked her down -- Nyoni wracked with nerves over whether the child could actually act.
"She was perfect," says Nyoni. "It was meant to be."
Maggie had never been to school, and the film team has since set up a crowdsourcing campaign for her education. The British Film Institute and FilmFour, which backed the production, have committed to supporting her until she turns 18.
"She's super smart," Nyoni says with a smile.
"She couldn't speak English before but now she's fluent, you can't get her to shut up."