Spoiler: Not everyone dies.
The USA President and chief scientist are black. They learn that massive geological upheavals are coming two years in advance, and participate in a foolish and corrupt conspiracy to save a few and let billions of people die.
The hero of the book is a white guy who wrote a novel that inspired the chief scientist to be more human. But his wife ditched him, and took the kids, because he had "tunnel vision" (according to her), and because she found another man who drives a fancier car. She continues to reject him, even after he saves her life multiple times.
The climax of the movie occurs when the good guys, including "Noah", get on a biblical "ark" with pairs of elephants and giraffes, a "tidal wave" washes them into the Himalayan mountains, and they narrowly miss the peak of Mt. Everest. Meanwhile, the wild elephants and giraffes in Africa do just fine.
The hero seems to believe seems to believe in a flat Earth, as he flies from Los Vegas to China by way of Hawaii. When it seems that he is going to run out of fuel 1000 miles before his targets, he acts as if he is going to swim the rest of the way.
The scenario for the destruction of the Earth is Charles H. Hapgood's cataclysmic pole shift theory. You can read about it in his book, The Path of the Pole. He actually got Einstein for his 1953 book, saying:
In a polar region there is continual deposition of ice, which is not symmetrically distributed about the pole. The earth’s rotation acts on these unsymmetrically deposited masses, and produces centrifugal momentum that is transmitted to the rigid crust of the earth. The constantly increasing centrifugal momentum produced in this way will, when it has reached a certain point, produce a movement of the earth’s crust over the rest of the earth’s body ...I didn't know that Einstein was a sucker for this crackpot stuff.