They left behind everything that mattered to them-- friends, lovers, country-- to journey to the stars. Now Sergeant Flynn Taggart and Pfc. Arlene Sanders, USMC, have reached their destination... the homeworld of the demon invaders who destroyed Earth. But there, they find a scene of destruction that rivals any they left back on Earth. And suddenly, "Fly" and Arlene find themselves face-to-face with an even deadlier enemy than the demons they came to fight. The war for Earth is over. But the battle for the stars has just begun...

The Gates were there on Phobos when mankind first arrived. Inert, unyielding, impossibly alien constructs, for twenty years they sat lifeless, mute testaments to their long-vanished creators, their secrets hidden. Then one day, they sprang to life...
Meet Corporal Flynn Taggart, United States Marine Corps; serial number 888-23-9912. He's the best warrior the twenty-first century has to offer, which is a damn good thing. Because Flynn Taggart is all that's standing between the hell that just dropped in on Mars and an unsuspectingg planet Earth...