The scourge is threatening the last Green Zone on Earth. The dying city is under control of a ruthless leader determined to seize the last of the food. Wren is part of a band of outcasts who steal to help struggling survivors. They travel beneath the city by way of old train tunnels to avoid roaming militias on the streets above. When the news comes that the toxic barrier holding the scourge back is breaking down, the outcasts must find a way to help those that are left. The last person Wren would have suspected, one she has grown to love, holds the key to their survival. But he may have to sacrifice himself to help them all.