It came without warning, but humans were not the target.
An apocalyptic scourge has destroyed all plant life. Surrounded by toxic chemical barriers to keep the scourge out, the last of the human race live in the few remaining Green Zones. Sixteen-year-old Iris is part of a group of Drifters who fight to survive while evading the lawless groups that prey upon them. Desperate to find safety, they forage small, deserted towns and avoid the dominant city of their zone where corruption and starvation rule. But time is running out, and Iris discovers the key to their survival may come from an unexpected source that will change their lives forever.