I worked for the Umbrella Corporation, the largest and most powerful commercial entity in the world. I was head of security at a secret high-tech facility called the Hive, a giant underground laboratory developing experimental, viral weaponry. There was an incident. A virus escaped. A lot of people died. The trouble was, they didn't stay dead. The computer that controlled the Hive was a state-of-the-art artificial intelligence: the Red Queen. The Red Queen responded to the threat of the viral outbreak in an extreme way. She went homicidal.
