Before the Flood is a new National Geographic documentary in which Leonardo DiCaprio assumes the role of a daring environmental investigator who sets out to reveal the impact of climate change, seeking practical ways in which we can work toward preventing the demise of endangered species, native communities and delicate ecosystems all over the planet. On the investigative journey, the actor has a chance to discuss the topic with some of today’s most prominent researchers and public figures including President Barack Obama and Elon Musk, CEO of Tesla.

This powerful presentation is the flagship for NatGeo’s recently declared initiative aimed at raising awareness of how the Earth is being affected by climate change. In one day, the feature accumulated over a million views during its exclusive free-presentation on YouTube. For those of you with cable providers, the documentary can now be viewed online at or on the NatGeo television network (check your local listings). Watch the trailer for Before the Flood below.