A professor takes six strangers hostage in a steam room and will only release them if a newspaper publishes a paper he wrote on global warming.

When global warming triggers the onset of a new Ice Age, tornadoes flatten Los Angeles, a tidal wave engulfs New York City and the entire Northern Hemisphere begins to freeze solid. Now, climatologist Jack Hall, his son Sam, and a small band of survivors must ride out the growing superstorm and stay alive in the face of an enemy more powerful and relentless than anything anyone has ever encountered: Mother Nature.