In the small town of Heron Key, where the relationships are as tangled as the mangrove roots in the swamp, everyone is preparing for the 4th of July barbecue, unaware that their world is about to change for ever. Missy, maid to the Kincaid family, feels she has wasted her life pining for Henry, who went to fight on the battlefields of France. Now he has returned with a group of other desperate, destitute veterans, unsure of his future, ashamed of his past.

When a white woman is found beaten nearly to death, suspicion falls on Henry. As the tensions rise, the barometer starts to plummet. But nothing can prepare them for what is coming. For far out over the Atlantic, the greatest storm ever to strike North America is heading their way...