...an effective and impassioned documentary.

This is well-researched, clearly articulated, and quite frankly terrifying stuff. Before the Flood makes you want to slap people in the face with your knowledge.

It should all resemble a vanity project except for one thing: The film lays out the case for reform with steadfast rigor.

The documentary, infusing interviews with powerful visuals, occasionally echoes the concerns of the protagonist. However, DiCaprio is most often an observer, an ant exploring the elephant’s body.