An urgent documentary inspires a soundtrack dream team. Before the Flood finds duo Trent Reznor and Atticus Ross (The Social Network) joining forces with fellow Oscar winner Gustavo Santaolalla (Brokeback Mountain, Babel) and Scottish post-rock outfit Mogwai (Zidane: A 21st Century Portrait) for a collection of soundscapes that—alternately unsettling and breathtakingly beautiful—evoke the scale and horror of global climate change.