John Raimi is assigned to infiltrate the Volks Corporation in Southern France. This corporation specializes in weapons but has been conducting bizarre experiments. John becomes a part of one of those experiments, and his spirit is separated from his body. As a ghost, he must possess other beings to find out what happened to his body. John has to find his body before it perishes.

Players start the game as John Raimi in human form. The game plays as though it is a regular first-person shooter. Players in human form can strafe, aim, run, and shoot enemies. In spirit form, they must possess people or animals to keep from being pulled into the afterlife; they can also drain the life from plants. To possess a being, first players have to frighten it. Players achieve this by possessing objects in the environment and making them do strange things.