The Unbelievers follows renowned scientists Richard Dawkins and Lawrence Krauss across the globe as they speak publicly about the importance of science and reason in the modern world – encouraging others to cast off antiquated religious and politically motivated approaches toward important current issues. The film includes interviews with celebrities and other influential people who support the work of these controversial speakers, including: Ricky Gervais, Woody Allen, Cameron Diaz, Stephen Hawking, Sarah Silverman, Bill Pullman, Werner Herzog, Bill Maher, Stephen Colbert,, Eddie Izzard, Ian McEwan, Adam Savage, Dan Dennett, James Randi, Cormac McCarthy, Paul Provenza, James Morrison, Michael Shermer, David Silverman, …and more.