The specter of celebrity activism hangs heavily over “Before the Flood,” Fisher Stevens’ documentary travelogue of Leonardo DiCaprio’s endeavors to combat global climate change. Yet at times, that also provides its greatest strength, as the actor uses his clout to coerce such major world figures as Barack Obama and Pope Francis into appearing on camera, and uses his own admitted lack of scientific background to his advantage, acting as a plainspoken everyman guide to some extremely complicated concepts. Handsomely shot and entertainingly paced, “Before the Flood” may not tackle too much new ground, but given the sincerity of its message, its ability to assemble such a watchable and comprehensive account gives it an undeniable urgency.  

“Before the Flood” begins with essentially two prologues. One features DiCaprio in voiceover talking about his early childhood, in particular the fact that he grew up with a print of Hieronymus Bosch’s “The Garden of Earthly Delights” hanging above his bed, which helped instill an awareness of social and environmental degradation from a young age. The second features a procession of conservative talking heads – Sean Hannity, Bill O’Reilly, et al – ridiculing DiCaprio’s environmentalist bonafides. It’s an effective double-barreled introduction, offering both an unusually personal glimpse into the actor’s thought process, and a hint of what he’s up against.

The meat of the film, however, concerns DiCaprio’s role as a UN messenger of peace, an assignment for which he travels from the oil fields of Alberta to the smog-choked streets of Shanghai, not to mention India, Polynesia, Greenland, the Vatican, and the White House to interview various experts about the now-unequivocal evidence that the earth’s changing climate will have – and indeed, is already starting to have – catastrophic consequences on human life. (He also visits with Alejandro Inarritu on the set of “The Revenant,” and those brief scenes, along with DiCaprio’s film-ending speech to the General Assembly, occasionally make the film resemble an extension of his 2015 Oscar campaign.)

On the whole, however, DiCaprio is a highly effective audience surrogate, asking scientists and leaders the sorts of to-the-point questions that many viewers might well have for themselves. He’s not afraid to sometimes appear uninformed, nor to acknowledge that his own carbon footprint is certainly larger than most. In fact, perhaps the film’s most intellectually stimulating moment comes during a visit to India, when he’s challenged on his own America-centric biases by activist Sunita Narain, who poses a difficult question: How can a nation like the U.S. ask a nation like India to risk its own, more tenuous, economic development with environmental measures that the U.S. itself has been hesitant to adopt?

But where the film succeeds the most is by focusing on the ground-level victims of climate change, whether the polar bears of the Arctic, or the inhabitants of island nations like Kiribati, whose former president Anote Tong uses phrases like “relocation with dignity” when planning for the uneasy future of his own homeland. Stevens keeps the film moving swiftly, alternating between images of inspiring beauty and horrifying dread, and the music – from Atticus Ross, Trent Reznor, Mogwai, and Gustavo Santaolalla – is a low-key achievement on its own.

Film Review: ‘Before the Flood’

Reviewed at Toronto Film Festival (TIFF Docs), September 10, 2016. Running time: 93 MINS.

  • Production: A National Geographic, Ratpac Documentary Films presentation of an Appian Way production in association with Insurgent Docs, Diamond Docs. Produced by Leonardo DiCaprio, Fisher Stevens, Trevor Davidoski, Jennifer Davisson, Brett Ratner, James Packer. Executive producers, Martin Scorsese, Adam Bardach, Mark Monroe, Zara Duffy.
  • Crew: Directed by Fisher Stevens. Screenplay, Mark Monroe. Camera (color), Antonio Rossi. Editors, Geoffrey Richman, Ben Sozanski, Abhay Sofsky, Brett Banks.
  • With: Leonardo DiCaprio, Barack Obama, Pope Francis, Ban Ki-moon, Alejandro G. Inarritu, Elon Musk, Sunita Narain, Anote Tong, Piers Sellers