When it premiered at the Sundance Film Festival in 2006, An Inconvenient Truth — the blockbuster documentary about former Vice President Al Gore’s crusade to draw attention to the threat of global warming — received three standing ovations, as noted in a trailer embedded below.

The film went on to gross nearly $50 million worldwide and win two Academy Awards. Gore would share the 2007 Nobel Peace Prize with a U.N. panel in recognition of their work to draw attention to what the commission called “the greatest challenge we’ve ever faced.”

“The climate crisis is not a political issue,” Gore said in a statement after the prize was announced. “It is a moral and spiritual challenge to all of humanity.”

In little time, it seemed as though the film had succeeded in galvanizing the general public around the need to address the threat of global warming, re-energizing the environmental movement and making Gore the cause’s public face, its celebrity icon.

And so when the backlash against climate change gained traction, it was in some ways manifested in a personal backlash against the former Democratic politician who had long irked the right, as illustrated in the above clip from tonight’s broadcast Climate of Doubt.

“Al Gore was the perfect proponent and leader of the global warming alarmists because he’s a very politically divisive and controversial,” Myron Ebell, director of the Center for Energy and Environment, told FRONTLINE correspondent John Hockenberry. “He was a wonderful target for our side.”

Personalizing the attacks on Gore were part of an approach that was embraced and amplified by friendly media, and part of a broad strategy to undermine public acceptance of a global scientific consensus.

Tonight, FRONTLINE explores the inner workings of the movement that changed the political debate around climate change. How did it happen? And who’s behind it? We hope you’ll watch.