Keith J. Snyder is a policeman hired to provide security for a new horror-themed casino called the Desert Moon. Suddenly a fire breaks out and a mysterious black liquid starts to pour out of the water sprinklers, turning people into vampires. Now Keith must find his way out of the casino and also try saving as many people as he can while trying to figure out what caused the transforming black liquid from happening.

The game involves shooting the vampires with an anesthetic dart gun and then sprinkling them with white water to turn them back to the normal humans they once were. The player can also choose to kill them instead of saving them by shooting the vampires with lethal weapons. There are also other types of enemies, such as vampire bats, that must be killed also. The usual survival horror conventions appear here such as item boxes,droves of enemies, keys to locate, and puzzles which require searching for items to solve them.

There are minigames set in a casino, like roulette and slot machines. The money won in these games can be used to buy food and drinks, the in-game recovery items.