Leonardo DiCaprio sat down with The Hollywood Reporter and a handful of select film publications at the Hotel du Cap in Cannes on Saturday to discuss his upcoming environmental documentary "The 11th Hour." The film, which premiered in a special Out of Competition screening Saturday at the Festival de Cannes, uses a barrage of images and reams of interviews with the world's top environmental scientists to paint a bleak but still optimistic picture of the fate of our planet. "Hour" was directed by sister Nadia Conners and Leila Conners Petersen, who wrote the script with DiCaprio. What was the most...