The structure of the series was apparent in the first book, Mister Monday (2003): seven books to read; seven keys to find; seven deadly sins to banish (the unfaithful Trustees); and seven saintly virtues to rescue (the parts of the Will of the Architect). Nix has remained true to this composition.

In the sixth instalment, Superior Saturday, the action intensifies as Arthur goes on the offensive, plotting his incursion into Saturday’s demesne, the Upper House. Arthur’s home and family are threatened by a nuclear strike, Nothing is encroaching on the epicentre of existence, and Arthur is turning into an immortal Denizen. The latter involves more than physical changes; Arthur tests the limits of the Will’s control over him and resists turning into an arrogant, heartless, and ultimately alien creature. In other words, Arthur has just hit puberty.

It is refreshing that Nix, even in later books in the series, doesn’t bulk up his plots with waffle. His descriptions are concrete and aided by instantly recognisable metaphors, and prior events are summarised without stalling the action.  Superior Saturday does feel unfinished compared with the previous, tightly structured titles in the series, and it seems odd that Nix doesn’t trust his readers to follow him into the final book (Lord Sunday, due for release in 2009), instead relying on an incomplete narrative in the penultimate instalment to draw them into the conclusion. Still, this won’t discourage fans. Let us hope that Nix can restrain his fantasy for one more book.