Knee-Deep in the Dead (novel)

Knee-Deep in the Dead is a novelization of Doom, and was written by Dafydd ab Hugh and Brad Linaweaver as the first book in the series based on Doom and Doom II: Hell on Earth.

Book Description
''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 unsuspecting planet Earth...''

Plot Summary
During an operation in the Middle Eastern country of Kefiristan, Fox Company leader Lt. Weems orders his men to open fire on civilians. Flynn "Fly" Taggart, the "Doomguy", attacks him.

Before he can be sent for court martial, however, Fox Company is called to the UAC research facility on Phobos to deal with a disturbance. Fly is kept prisoner by two Privates while the rest are sent off. This may be Fly's saving grace, as Fox Company is wiped out by the invading forces. Escaping, Fly encounters several zombies, then a run-in with an Imp (Knee-Deep in the Dead, with the imp within what is recognizably E1M1).

Moving deeper into the complex, Fly finds more monsters, as well as "A.S." arrow marks on the walls - PFC Arlene Sanders, his best friend, has survived and is leaving him directions. Ultimately, Fly reaches the two Barons, defeats them, and is transported to Deimos Base, completely naked (The Shores of Hell). On Deimos, he finds Arlene, regains clothes and weapons, and the two eventually find the Cyberdemon before defeating it. Teleported again, the two find themselves inside a gigantic fleshy enclosure, and field-strip corpses for clothes and weapons once more (Inferno).

Here, they meet Bill Ritch, a UAC computer programmer whom the Spider Mastermind captured and tried to interrogate. The three make their way through this complex, ultimately defeating the Spider Mastermind, at the cost of Bill Ritch's life.

Returning to the surface, they find they are still on Deimos, which has been moved to Earth orbit. However, the giant dome that holds in the oxygen has cracked. Worst of all, they can see explosions all over Earth's surface - the invasion has already reached Earth.