Plot

Extermination takes place on December 24, 2005, at a top secret American research facility in Antarctica. The game focuses on U.S. Marine Corp's Force Recon member Sergeant Dennis Riley, as part of "Team Red Light". His squad receives a distress call from the aforementioned base named Fort Stewart. The distress call requests an immediate air strike on the base. Instead, Team Red Light is sent in via C-17 to investigate. En route, the plane malfunctions, scattering the team and crashing into the tundra. Their new objective is to regroup at Ground Facility Building B. Dennis, along with teammate Roger Grigman, arrive outside the fort. The two enter the fort through the ventilation shaft. After discovering that "this place looks like a battlefield," they try to get the drawbridge lowered to continue on to Building B. Upon making their way to the other side, Roger comes under attack by Hydras. He becomes infected and rapidly mutates in front of Dennis. A mysterious woman in a contamination suit enters and fires at Roger, seemingly killing him. She throws Dennis an extra magazine for his rifle, and an MTS vaccine, shouting: "Use it if you don't want to end up like your friend!" Thereafter, she orders him to tell his team to escape the fort.