As long as the undead hordes of the Inferi Scourge howl outside the dying city, the last remaining humans struggle to survive inside The Bastion. Vanguard Maria Martinez has lived her entire life within the towering walls. Her only refuge from the overcrowded streets, rolling blackouts, and food shortages is in the arms of Officer Dwayne Reichardt. Then Maria is summoned to meet with a mysterious representative from the Science Warfare Division and is offered the opportunity to finally destroy the Inferi Scourge and reclaim the land and resources in the valley beyond the wall. If she succeeds, the city may be saved.