He has expanded through the very air we breathe. He's galvanized activists around the globe to fight him and stymied the world's political leaders. Meet Mr. CO2: carbon dioxide, the primary cause of climate change.

MR. CO2 opens in Copenhagen, where the world's political leaders gather in December 2009 to try and hammer out a new carbon treaty to replace the Kyoto Accord. Joining them are activists and climate scientists, on-hand to press for action. They include Rajendra K. Pachauri, Chair of the International Panel on Climate Change, and Bill McKibben, founder of a movement aimed at lowering atmospheric carbon, who says at the conference, "we are past the red line, the real debate is between human beings on the one hand, and physics and chemistry on the other."

Traveling from the Copenhagen negotiations to China, Australia, and the United States, MR. CO2 explores the scope of the challenge. In China we meet Ren Runhu, director of the Lu'An Mine, which producers 55 million metric tons of coal a year. Even though 5,000 miners die in China's coal mines yearly, the industry is flourishing. In his gleaming office—a far cry from the working conditions of the black-faced miners—he explains that coal is just too important to Chinese industry.

Meanwhile, the world's richest people—North Americans and Europeans—continue to be responsible for staggeringly high per capita emissions.

Featuring climate scientists, activists, coal producers and high-stakes negotiators, MR. CO2 makes clear that there will be no easy answers when it comes to solving the climate crisis. Clean coal is more propaganda than reality, and carbon sequestration and storage carry their own environmental risks.

It seems that—in the short-term at least—Mr. CO2 will continue to have a bright future indeed.