Commentator-comic Bill Maher plays devil's advocate with religion as he talks to believers about their faith. Traveling around the world, Maher examines the tenets of Christianity, Judaism and Islam and raises questions about homosexuality, proof of Christ's existence, Jewish Sabbath laws, violent Muslim extremists.
| Actor | Role |
|---|---|
 Bill MaherSelf - Host/Narrator | Self - Host/Narrator |
 Jose Luis De Jesus MirandaSelf | Self |
| AAndrew NewbergSelf | Self |
| SSteve BurgSelf | Self |
 Tal BachmanSelf | Self |
| JJonathan BouldenSelf | Self |
 Francis CollinsSelf | Self |
| GGeorge CoyneSelf | Self |
| BBenjamin CremeSelf | Self |
| JJeremiah CummingsSelf | Self |
| FFatima ElatikSelf | Self |
| YYahuda EtzionSelf | Self |
| RReginald FosterSelf | Self |
| MMohamed Junas GaffarSelf | Self |
| BBill GardinerSelf | Self |
 Ted HaggardSelf (archive footage) | Self (archive footage) |
| KKen HamSelf | Self |
 Larry CharlesSelf | Self |
| JJerry FalwellSelf (archive footage) | Self (archive footage) |
 Billy GibbonsSelf (archive footage) | Self (archive footage) |
 Dusty HillSelf (archive footage) | Self (archive footage) |
 Michael JacksonSelf (archive footage) | Self (archive footage) |
 John McCainSelf (archive footage) | Self (archive footage) |
 Britney SpearsSelf (archive footage) | Self (archive footage) |
 Joe LiebermanSelf (archive footage) | Self (archive footage) |