Egypt's "zar" ceremony is a healing cult that drives out possessing spirits, sometimes called jinns or demons, that cause malady. Apart from being an ancient tradition, considered pagan practice by Islam, it is an essential part of the Egyptian culture, accompanied by drums and dancing by women who found a place to shine amid strict patriarchy.

"We're not quacks or witches," said Umm Sameh, aged in her 70s, with kohl-lined eyes, large hoops swaying in her ears, and gold bracelets tinkling on her arms. "The singing is spiritual and brings out negative energies," said the lead singer of the Mazaher ensemble, adding that they also perform prayers from Islam's mystic Sufi practices.

Traditionally, the zar ritual would last several days and include animal sacrifices. But no blood is spilled at Cairo's Makan Cultural Centre, where the group performs to the delight of foreign and local guests. The audience is bewitched by Umm Sameh's voice and nods their heads to the drumbeat.

In a patriarchal society where women face frequent discrimination, zar ceremonies are among the few cultural practices in which they take center stage. Umm Sameh said she learned the ritual from age 11 from her mother and grandmother. Six decades later, she recites the same lyrics to the same tunes – all from memory, she adds proudly, because she has "inherited them and grown up with them."

"Zar is a very old healing ritual, a bit like medical treatment," said Ahmed al-Maghraby, founder of Mazaher, which he says is Egypt's last group to perform zar in public. He set up the Makan performance space 22 years ago "to preserve this cultural heritage and archive local music from all over Egypt." It was a tough feat, he said, because zar has historically been derided by devout Muslims as a pagan practice, and rejected by modernizing state authorities as a backward rural tradition.

"Middle Eastern and Egyptian society regard everything local with disgust," lamented Maghraby. He said it was foreign tourists who first brought Egyptians to the shows, who he remembered used to say, "No! There's jinn and blood!'"

"For them, the zar was always something sinful," he added.

Ensemble member Abou Samra said, "people have a very negative idea of zar because of the movies" in Egypt, long regarded as the Hollywood of the Arab world. In one of them, the 1987 horror movie "Al Taweeza" (The Curse), superstars Youssra and Tahia Carioca contorted themselves, drenched in fake blood, and emitting shrill cries. But zar is "an art like all other arts," said Abou Samra, who plays the tamboura, a six-string lyre. "We have to let go of these stereotypes."

Times are indeed changing. The ensemble, whose musicians and dancers were all over 60, has brought in a new member.

Azza Mazaher, who grew up watching her mother Umm Hassan do percussion, now also drums and energizes the show as she dances across the stage. Azza said the group now performs in both the old and new ways.

"If someone feels sick and the doctors can't find a treatment, we can hold a ceremony," she told Agence France-Press (AFP).

"But here, we're performing a light piece of folklore, so people can discover it, understand it and enjoy it," she added.

Mazaher has taken part in several European festivals, and more Egyptians are flocking to their Cairo performances, appreciative of the home-grown art form.

Mariam Essawi, an audience member in her 20s, said: "They look like us, they represent us. Zar is part of our history and our cultural heritage. Strangely, we don't know it."