Riley wants to rebuild her relationship with her mother and little sister, who are shut-ins due to her sister's illness. When Riley realizes her sister may not be sick, her mother will stop at nothing to keep her daughters with her forever.

When an energy experiment goes haywire, a rash of massive hurricanes rips across North America. A high school science teacher must get his family to safety before the hurricanes merge, creating a "hypercane" with the power to wipe the US off the map.