Cannibalism is still alive in the film 'The Green Inferno'

After almost seven years, horror director Eli Roth returns to the big screen with a new, more twisted and blood-soaked film "The Green Inferno."

On his comeback, he's shifting his lens to another popular held nightmare—that the jungles are still full of voracious man-eaters—to whom white and ideally virginal flesh is a delicacy.

The Green Inferno tells the story of what happens during “slacktivism," the well-meaning social-media response to global catastrophesturns deadly deep in a South American rainforest.

Charismatic young activist Alejandro inspires his fellow students with a rousing story about an untouched Peruvian jungle about to be destroyed by a greedy energy company looking to exploit its natural resources. Soon eight young protestors, including Justine, the daughter of a United Nations official, and her roommate Kaycee, are headed to this remote Amazon village to ward off the bulldozers.

But when their small plane crashes in the jungle, they are horrified to discover that the tribe they came to still practices the ancient rite of cannibalism.

To make the film work Roth cast a real Peruvian tribe called the Callanayacu tribe he discovered deep in the Amazon while scouting for a location. The Callanayacu tribe lived a life that has not changed for for hundreds of years, did not know about electricity and have never seen or heard about movies or TV.

So to give them an idea of what they would be doing and imitating, Roth and crew brought a generator, a TV and introduce the tribe to movies. He made them watch the 1980 grindhouse film, "Cannibal Holocaust."

“We had to explain to them conceptually what a movie was, and showed them Cannibal Holocaust—and they thought it was the funniest thing that they had ever seen---but we had to know whether they were down with it to let us in their village,” Roth said in an interview.

For the main character of Justine, Roth cast Chilean-born model-turned-actress LorenzaIzzo. “Lorenza has an amazing combination of riveting on-screen presence, incredible natural beauty and a sweetness that makes her sympathetic and likeable,” says the director.

Playing Justine’s roommate Kaycee is singer-songwriter Sky Ferreira. Other members of the ensemble include Daryl Sabara, Kirby Bliss Blanton, Magda Apanowicz and newcomer Aaron Burns. Sabara, who plays another student, Lars, was impressed with Roth’s lean, fast- moving shooting style. Rounding out the cast are Ariel Levy, NicolásMartínez and IgnaciaAllamand.

"The Green Inferno," opens in cinemas nationwide beginning Sept. 23, 2015 from Solar Pictures.