Six months pregnant, Avery is nearly scammed out of her baby's trust fund by her cheating husband Ethan and his mistress Bailey. Just in time, she hears her unborn son's voice,revealing their betrayal and the coming apocalypse: six months of endless rain that will flood the world.
Avery tricks the couple, secures her money, and turns her parents' mountain homestead into an impenetrable fortress before the storm hits. She leaves Ethan and Bailey to suffer in the toxic rain, avenging her past death.
As the apocalypse unfolds, Avery and her son Noah (who retains his danger-warning ability) protect their family, take in good survivors, ally with the military, and fight mutated creatures and raiders. When FEMA offers relocation to a central shelter, Avery chooses to stay in the home she built, forging a new future with her loved ones.
