The Whispering Vault is a roleplaying game where the characters are Stalkers, beings who have transcended their humanity to act as agents for the beings that maintain reality. Regrettably, sometimes those beings (the Unbidden) fall from their station, for various reasons, and must be dealt with, for which the Stalkers are summoned. The Avatars of the Stalkers are placed into mortal shells (Vessels) to be sent down to the mortal reality, where they must retrieve the fallen being before they corrupt reality.
Stalkers are limited when in the mortal reality in that they cannot openly use their powers, while the beings they stalk can: Stalkers, therefore, have to use their powers in such ways as to make them seem natural. (For example, Emma Steele will reach into her sleeve or behind her back to use her Conjuration Discipline produce a weapon.) Using powers blatantly before witnesses can cause a punitive reaction from reality, somethings Stalkers do their best to avoid in order to complete their mission.
Stalkers all have their personal Domain: the place where they rest, the place they in which are most comfortable, the place that reflects their very nature.