You play Parker, an inexperienced miner who's recently begun working in a huge mining complex on Mars, run by the Ultor Corporation. Far from the workers' Utopia you were led to believe from Ultor's advertising on Earth, the mines are an awful place. Living conditions are terrible, the work environment is dangerous, Ultor runs the place like a prison camp, and there's a disease the miners call the Plague that's running rampant, disfiguring and killing miners. Tension is high; there've been strikes and riots, brutally suppressed by Ultor security. The whole complex feels like it's going to explode; all it needs is a spark. Unfortunately, you provide flint and striker. As your shift ends one day, an Ultor guard brutally assaults you. It's kill or be killed and you fight back. The next thing you know, Ultor security is freaking out, killing miners on sight, the miners are fighting back in a full-scale rebellion, and you are now #1 on Ultor's Most Wanted list. But you're a hero to the miners and chicks dig you. An Ultor tech named Hendrix contacts you, claiming to be on your side and offering to help guide you to asfety. You hear about miners going to take over a ship and escape and that sounds good to you. You arrive at the docking bay just in time to see the captured ship take off and get blown out of the sky. You've heard of Eos and the Red Faction group she formed to oppose Ultor and Hendrix tries to help you reach them (matter of fact, you were a probationary member of the Red Faction; that's where you received your weapons training). But your way down to the rebel base is cut off. Eos gets in touch with you and asks you to help the Red Faction defeat Ultor. Your first task involves disabling enough of Ultor's operations in this part of the mines to enable the Red Faction to launch a counterattack against Ultor's troops. Eos's sent squads of miners to accomplish this task, but they keep getting wiped out. You go in and get the job done. As a reward, she's got another job for you. She wants you to capture Gryphon, the Deputy Administrator of the mines. She thinks they can force him to not only tell what's going on with the Plague (which the miners suspect Ultor's behind) but also how to get a message out to the EDF fleet (Earth Defense Forces, which have been waiting for an excuse to shut Ultor down). So you go up to executive country, slip on a suit, sneak through the Admin level, and grab Gryphon. Turns out he sees everything Ultor's done blowing up in its face and he's eager to turn rat in classic style. He leads you to a secret weapons development lab where you grab ahold of the latest in Ultor military hardware. After some trials and tribulations, you turn Gryphon over to a squad of miners, who take Gryphon down to the Red Faction base. Gryphon claims that a scientist named Capek is behind the Plague that's running wild through the miner population. So now you go after him. A couple of levels later, you find him and confront him in his labs. It's a big boss fight with Capek using weapons he's developed via his researches. Eos joins you and together you battle Capek. Unfortunately, a self-destruct mechanism, linked to Capek, is set off (to prevent the incriminating evidence in the lab from falling into the wrong hands). With the lab ready to blow around you, Eos sends you off to continue the fight while she tries desperately to find the formula for the antidote before the labs blow up. Does she escape with her life and the formula? You don't know and only time with tell.