The film begins by retelling the biblical story of Noah building an ark to survive a coming flood ordered by God to purge humanity of its wickedness. Noah has visions warning of the coming flood and is told by his grandfather Methuselah that he must build an ark. Noah, with the help of stone giant angels called Watchers, builds the ark and collects animal pairs. As the floodwaters rise, Noah's family and the animals escape aboard the ark as the rest of humanity perishes in the flood. After the waters recede, Noah's family disembarks and he performs a ritual blessing the next generation to begin anew.