As intense heat waves and unusually powerful storms strike various parts of the Earth, it becomes evident to scientist Jonathan Holmes that the world may be experiencing a runaway greenhouse effect. When the U.S. Navy discovers that the West Antarctic Ice Sheet is about to collapse, the Pentagon implements a top secret plan to evacuate millions of refugees from the Pacific island nations, the Caribbean, and from the low-lying coastal areas of America, but as the government moves into action, a group of violent environmentalists decides to take matters into their own hands.