Not even the immune are safe. A psychopath has kidnapped Finn's twin brother and promises to infect him with the Flense, an artificial virus that turns the vulnerable into vicious killing machines with a taste for human flesh. But before he can rescue his brother, Finn is betrayed by someone close and is returned to the madman's compound, where he awaits a similar fate. For the other Bunker 8 survivors, it's a race against time to find the elusive twelfth bunker and the promise of a cure. Will they prevail soon enough to help Finn?