Denizens of the House

The House is a domain that serves as the center of the universe in The Keys to the Kingdom series by Australian author Garth Nix. Anything in creation not in the House — such as Earth, the Solar System, and, indeed, this Universe — is part of the Secondary Realms. The House is divided into seven demesnes, each ruled by a master who shares their name with a day of the week — the Trustees, or Morrow Days. The demesnes, in the order Arthur Penhaligon has claimed them, are as follows: the Lower House, the Far Reaches, the Border Sea, the Great Maze, the Middle House, the Upper House and the Incomparable Gardens.

The House's physical appearance in the Secondary Realms is described as a vast building featuring many different architectural styles, which often appear to be brought together at random. Its physical location differs; Arthur first sees it near his own residence, and his friend Leaf sees it above a hospital. Arthur, Leaf, and Leaf's ally Sylvie are the only mortals shown to see the House, each by a different means: Arthur can see it presumably because he is the Heir of the Architect; Sylvie requires special glasses given to Leaf by the House Sorcerer Dr. Scamandros; and Leaf appears able to see it without aid. It is her belief that she has inherited powers of extrasensory perception from her grandmother, whom she thinks to have been a witch, but this has not been confirmed. A possible alternative suggests that her immersion in the House (which occurred prior to her view of it from outside) enabled her to see it.

The House has seven demesnes: the Lower House, Far Reaches, Border Sea, Great Maze, Middle House, Upper House, and the Incomparable Gardens. The Gardens are the uppermost part of the House. The Lower Coal Cellar acts as a basement; it is infinite and houses the ancient prison of the Old One.

The divine figure known as the Architect created the House to record, without intervening on any behalf, all that happened in the Secondary Realms (that is, the Universe at large). Most Denizens of the House believe that the House was created first, but this is only true of the Incomparable Gardens. Having created House, Realms, and a Law that would prevent Denizens from intervening in the actions of mortal creatures, the Architect vanished and is not shown again. The Law is not binding however (although in 'Grim Tuesday', Arthur repels two agents from the House by invoking the Original Law, along with his latent power gained from the use of the First Key); it can be broken, as all of the Architect's Trustees have done at one time or another, making themselves the villains of the story. A Trustee can only enter the Secondary Realms on their "day", i.e. Mister Monday can only enter the Secondary Realms on a Monday. Furthermore, the Superior Denizens (Dawn, Noon, and Dusk) of each day can only enter the Secondary Realms on the hour of their name (a Noon, for example, can only enter during the hour from 12:00pm to 1:00pm).

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