You play as Jill Valentine. After the mansion incident, the S.T.A.R.S team went back to the RPD, but after a few days Raccoon City was devastated by a strange virus, turning everything into monsters. The Army has a plan, but until then you must get out of the city, before it's too late.

It all began as an ordinary day in September...
An ordinary day in Raccoon City, a city controlled by Umbrella.
No one dared to opposed them... and that lack of strength
would ultimately lead to their destruction. I suppose they had to suffer the
consequences for their actions, but there would be no forgiveness.
If only they had the courage to fight. It’s true once the
wheels of justice began to turn, nothing can stop them. Nothing.It was Raccoon City’s last chance... and my last chance...
My last escape.