Hosted and produced by Leonardo DiCaprio, "11th Hour" is a frightening overview of the world we inhabit and frequently take for granted. It's a 90-minute-long plea from the actor, arguably one of the best of his generation, and bleeds the same color of passion DiCaprio often reserves for his acting endeavors. Certainly the film could be lumped in with Al Gore's "An Inconvenient Truth," but "Hour" is a different beast of the documentary, even if the two films share the same airspace when it comes to compassion for all things green.

Where Gore simply decorated his PowerPoint presentation with ecological disaster stickers and charts, DiCaprio is heading toward traditional documentary high ground. "Hour," directed by Nadia Conners and Leila Conners Petersen, is a straightforward look at several threats facing climate and life, using a group of talking heads to illustrate the need to start taking these matters seriously. These aren't just any ordinary talking heads though; we meet Mikhail Gorbachev, Stephen Hawking, and David Suzuki, along with hordes of other scientists and assorted experts the filmmakers have gathered to discuss the topic at hand.

It's an impressive bunch, but much like "Truth," "Hour" can get drowsy at times from all the stasis. While brimming with cutting observations and engrossing fears about the future, "Hour" isn't a flashy film, and it occasionally dissolves into a lecture rather than an explosive and enlightening piece of eco-alarm. Of course, these moments are spare, but "Hour" has some undeniable pacing problems that come close to muting the impact of the final product.

Thankfully, there's enough horror out there in the world today to keep the film alive with unease. Surprisingly, "Hour" only dances with a more traditional serving of global warming terror for about 10 minutes. The rest of the picture is more concerned with raising awareness of pollution, deforestation, and overpopulation, calling into question the integrity of food and goods, and tracing the decline of overall health. The film also explores the impact of personal responsibility on the planet, while making sure to hurl some blood-red blame on the fur coats of big business and the government, who, no shocker here, are caught in the thick of uncontested corruption and greedy manipulation, unwilling to make the needed changes to ensure we all have some form of livable future.

"Hour" enrages and depresses for a good hour, using ample footage of our diseased planet, underlining the fragility of a world lost in the rabid foam of consumerism. There is a light at the end of this bleak tunnel (thank heavens), and soon "Hour" downshifts into hope mode, demonstrating that with willpower and perhaps some forceful political intervention, we can lick this beast called foreign oil and take off towards a greener future that doesn't include acidic skies and mass death on a mind-blowing scale. "Hour," even with its somewhat tedious presentation, has profound ideas to share, and in this naked intent lies a disturbing, chilling tale of a tomorrow we all can avoid through action and some good old-fashioned consideration.