Avenging Spirit

During a walk with his girlfriend, the player is ambushed by agents of a mysterious crime syndicate who take his girlfriend away and shoot him to death. Now, as a wandering spirit with the ability to possess most others, he is summoned by his girlfriend's father (who researches ghost energy) and is given a mission to save her from the mysterious crime syndicate that holds her hostage, enabling the player to rest in peace. (Wikipedia: The Free Encyclopedia, s.v. "Avenging Spirit")