 Jeff BridgesSelf - Narrator (voice) | Self - Narrator (voice) |
 Piers SellersSelf - NASA Astronaut & Research Scientist | Self - NASA Astronaut & Research Scientist |
 Wesley ClarkSelf - General, US Army (ret.); Former NATO Supreme Allied Cmdr. | Self - General, US Army (ret.); Former NATO Supreme Allied Cmdr. |
 Oren R. LyonsSelf - Dist Prof of American Studies, Onondaga Council of Chiefs | Self - Dist Prof of American Studies, Onondaga Council of Chiefs |
 Timothy MortonSelf - Philosopher & Author, 'Humankind' | Self - Philosopher & Author, 'Humankind' |
 Bob InglisSelf - Former Congressman (R), South Carolina | Self - Former Congressman (R), South Carolina |
| RRich PancostSelf - Professor of Biogeochemistry | Self - Professor of Biogeochemistry |
 Ruth GatesSelf - Marine Biologist; Dir. Hawaii Institute of Marine Biology | Self - Marine Biologist; Dir. Hawaii Institute of Marine Biology |
 Renée LertzmanSelf - Author, ‘Environmental Melancholia’ | Self - Author, ‘Environmental Melancholia’ |
| LLeonard MlodinowSelf - Physicist | Self - Physicist |
| BBruce HoodSelf - Prof of Developmental Psychology, Univ of Bristol, UK | Self - Prof of Developmental Psychology, Univ of Bristol, UK |
| MMark PlotkinSelf - Ethnobotanist, Amazon Conservation Team | Self - Ethnobotanist, Amazon Conservation Team |
| AAmy JacobsonSelf - Evolutionary Anthropologist, Human Behavioral Ecologist | Self - Evolutionary Anthropologist, Human Behavioral Ecologist |
| DDaniel GolemanSelf - Psychologist, Science Journalist, Author | Self - Psychologist, Science Journalist, Author |
 Stephan LewandowskySelf - Professor of Cognitive Psychology, University of Bristol | Self - Professor of Cognitive Psychology, University of Bristol |
 Nate HagensSelf - Director, Instit. for the Study of Energy & Our Future | Self - Director, Instit. for the Study of Energy & Our Future |
| JJoseph TainterSelf - Professor of Anthropology, Author | Self - Professor of Anthropology, Author |
| UUgo BardiSelf - Prof of Physical Chemistry, Univ of Florence, Italy | Self - Prof of Physical Chemistry, Univ of Florence, Italy |
| PPaul RobertsSelf - Journalist; Author, 'The Impulse Society' | Self - Journalist; Author, 'The Impulse Society' |
| IIan RobertsonSelf - Cognitive Neuroscientist, Trinity College, Univ of Dublin | Self - Cognitive Neuroscientist, Trinity College, Univ of Dublin |
