Earth faces catastrophic freezing, equatorial safe zone identified. Virologist with cure must reach it in 24 hours to save humanity from pandemic and deep freeze.

Already in the throes of a viral pandemic, a massive polar vortex threatens to cover nearly all of Earth in ice. When it's discovered the only chance of survival from the cold is a 100-mile temperate zone near the equator, a virologist, with the pandemic's only cure, must reach the safe zone within 24 hours if humanity is to have any hope of survival.