The film follows two lazy, misfit hunter-gatherers named Zed and Oh, played by Jack Black and Michael Cera, respectively, who are banished from their primitive tribe after Zed eats forbidden fruit from the Tree of Knowledge. They embark on a journey through the ancient world, encountering various biblical and historical figures, including Cain and Abel, Abraham and Isaac, and Sodom and Gomorrah. Along the way, they get involved in comical misadventures and learn valuable lessons about friendship, love, and the meaning of life.