When the Agent X virus first struck, the victims became voracious killers intent on contaminating every last soul. And X spread like mad... The entire eastern seaboard of the United States has been ravaged by the contagion, wiping out all signs of hope, faith, or rational thought. Off this desolate coast is a refitted nuclear sub, a 560-foot steel tomb cutting through dark waters and commandeered by a crew of survivors—including Sal DeLuca, who lost his father during their flight from Agent X. When he leads a team to scavenge for food and supplies on land, he comes across a squad of seemingly welcoming mercenaries. But he's about to find himself trapped between new terrors on the surface and mutiny below.