Marcus Fenix. War hero. Decorated Gear. Loyal son. Traitor. As the Locust Horde advances into one of humanity’s last bastions—Ephyra—after ten years of a bloody global war that has seen billions die, Marcus does the unthinkable: he defies Colonel Hoffman’s orders and abandons his post in the middle of the battle in a bid to rescue his father, weapons scientist Dr. Adam Fenix. But Adam is buried in the rubble of a ferocious assault on the Fenix estate, and Ephyra falls to the enemy. As the Coalition of Ordered Governments struggles to defend Sera’s surviving humans from the invading “grubs,” Marcus faces a court martial. Deserting his post in wartime means the death penalty. But his sentence is commuted to forty years in the COG’s most notorious prison—known as the Slab—where a prisoner’s life expectancy is less than two years.