For almost 15 years, the last Saturday in March goes dark. Millions of people in over 190 countries flip the switch for 60 minutes, to help illuminate one of the largest grass roots movements on the planet. Earth Hour has always drawn its power from the people, and organizers our counting on their support more than ever. "It is a dual crisis, it is climate change and bio- diversity loss and they ecascerbate each other", says Megan Leslie President and CEO of World Wild Life Canada. On this episode of The Big Blue Marble we learn how Earth Hour has evolved, it's less about the light and more about the fight. "it gets all of us to focus on one thing and politicans listen to that." adds Leslie.