'Really horrified': Oilsands under the spotlight in Leo DiCaprio's new climate change doc

Canada features prominently in Leonardo DiCaprio's new climate-change documentary Before The Floodand director Fisher Stevens said he was "really horrified" by scenes of the oilsands in northeastern Alberta.

"It does employ a lot of people," said Stevens of the oil industry, during an interview at the Toronto International Film Festival, where "Before the Flood" had its world premiere. The documentary will be screened in 171 countries, in 45 languages, when it debuts on the National Geographic Channel on Sunday.

"Look, we all want work, we all need jobs God knows. And it would be great if it was like: 'Now, we take all of these people and we replant all of that forest.' Wouldn't that be amazing?"

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"He called me and he said: 'Hey, man, the planet's getting worse and I want to make another climate-change movie, and I want you to do it with me'" recalled Stevens, an actor and filmmaker whose past environmentally focused projects include "Mission Blue" and "Racing Extinction" and working as a producer on the Oscar-winning documentary "The Cove."

"He said: 'Yeah, I'm willing to be in this one.' And I think he regretted that for sure at first. He wasn't used to having the cameras in his face like that, and he was quite uncomfortable at times, not having lines, not playing a character just being Leo.

"He's a wonderful person," Stevens added. "(I said to him): 'You're the guy. If ever we can use a movie to move the needle, you're the guy.'"

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The timing of the documentary's release is no coincidence. The duo was determined to have it completed in advance of the looming U.S. election.

"The Senate and the Congress, as you see in the film, is full of people on the payroll of the fossil fuel industry, and (who) are worried that they're going to lose their seats if they push the climate agenda," said Stevens.

"We're going to have some swing state screenings (and) get rid of these people if we can. It's really time. It's finally time that people wake up."

'We're not trying to preach to the converted'

Stevens said he was haunted by images of burning forests in Indonesia, where palm oil is produced for use in a vast range of products including cosmetics, food and household items.

"Very few people are profiting off of a huge part of the population being affected, and that's kind of like a theme in climate change."

But Stevens remained buoyed by positive trends that have emerged, pointing to renewable energy becoming more affordable, U.S. President Barack Obama speaking out on climate change, as well as Pope Francis's encyclical on the environment.

"We're not trying to preach to the converted. That wasn't our interest. We want to make a cool film, a film that people really drink in."