Walker Jameson, dishonored Recon Marine, has pulled off an impossible escape from Terminal Island Penitentiary. After starting a riot, he vanishes from his cell, leaving behind the body of a sadistic killer, and little else.

Deputy U.S. Marshal Tim Rackley, elite manhunter, must track Walker down. But uncertainty begins to color the mission the more that Rackley learns about his quarry, and the more he probes the death of Walker's sister, a suicide that looks increasingly like murder.

With the life of his young nephew hanging in the balance, Walker begins a bloody investigation that propels him through the dark underworld of a big pharmaceutical company and its cutting–edge therapeutic viruses. If Rackley hopes to stop the bloodshed, he must put the pieces together, even if it means battling a lethal opponent every inch his equal.