Watch: Celebrities and Activists Speak Out at the People's Climate March

Paul Bettany, Darren Aronofsky and more were among the 400,000 protesters in New York

The 400,000 protesters who participated in the People's Climate March on September 21st included some famous faces. We caught up with director Darren Aronofsky, actor Paul Bettany and more – and captured some of the most striking moments of the protest – as they marched through the streets of New York to demand a better tomorrow. "People don't march as much anymore, because they're uniting on the Internet," Aronofsky tells Rolling Stone. "It's great to get people out into the streets."