A young woman awakes trapped in an enclosed space. She has no idea who she is or how she got there. With only her instincts to guide her, she escapes her own confinement -- and finds she's not alone. She frees the others in the room and leads them into a corridor filled with the remains of a war long past. The farther these survivors travel, the worse are the horrors they confront. And as they slowly come to understand what this prison is, they realize that the worst and strangest possibilities they could have imagined don't even come close to the truth.