details:this mission is a little similar to Resident evil's missions,but less realistic.
Just to make it look better,i advice you to dowload (BioHazard Alert REMAKE 0.5) for the playa's skins,so quit being lazy & don't play the game with those old ugly san andreas skins.
Here's the materials for the ingame picture:grim' weapon pack v2 and v1,Cleo Zombie Alarm(only the skins inside the REvil.img),look for them in GTAinside.com.
The story is in the game,the rest of the story will be coming any days so sit back & wait.