Necropolis 2: Endurance
The second novel in The Shadow Wars.
The nightmare began on a little wasteland of a planet called Dis. Greg Bishop awoke with nothing but his name and a pistol. Stumbling through the rain, no memories of his past, he discovered a terrifying new enemy: the Undead. Mindless, ever-evolving creatures that exist merely to kill and reproduce.
With a handful of survivors, Greg escaped Dis, which was destroyed in a clean-up attempt by a secret branch of the government known only as Dark Ops. But his escape led him directly into their holding cells. Now, a prisoner aboard a ship where his enemies have complete control, Greg must find some way to escape once more.
Only this time it won't be so easy. Not only is Dark Ops in charge, reigned over by a sadistic scientist, but the Undead are onboard. And there's a third, unknown threat, lurking somewhere in the shadows, waiting to strike...