It's all started with a train ... On July 23, 1998, a train owned by Umbrella corp , the Ecliptic Express , comes under attack from a swarm of leeches. As the passengers and crew are attacked, a mysterious young man watches over the resulting chaos from a hillside. Two hours later, the Bravo Team of the Special Tactics And Rescue Service (S.T.A.R.S.) police force is sent to investigate a series of cannibalistic murders in the Arklay Mountains outside of Raccoon City. On the way to the scene, its helicopter has an engine failure and crash-lands in a forest. While searching the immediate area, Officer Rebecca Chambers of Bravo Team comes across the Express, now motionless, and explores it, only to find the passengers and crew transformed into zombies, unaware their transformation was a result of exposure to Umbrella's T-Virus contained within the leeches. As she explores the train for answers, she teams up with Billy Coen -a former Marine Force Reconnaissance officer, who was to be executed for killing 23 people until the military police van transporting him crashed within the region. Resident Evil Zero is the survival story of Rebecca and Billy and the origins of the T-Virus .