The Second Book in Garth Nix's Trilogy, The Keys to the Kingdom
At the end of the Mister Monday, Arthur had defeated Monday, and had taken control the Lower House, the realm of Mister Monday, and had handed control of it to the Will, and Suzy Turquoise Blue has assumed the position of Monday’s Teatime,the period of control between the hours of 4-6 in the afternoon, and Arthur returns home to claim a bit of well deserved rest.
However, this is not what happens in stories, so Arthur is rudely awakened by the Will, the main sorf of governing body of the House and it's Domains, informing him that the next of the Morrow Days, Grim Tuesday, has claimed all of the Lower House and it’s Denizens in payment for Monday’s debts to him. So Arthur is summoned back into the House.
Again, Arthur must travel throughout the house, and with the help of friends both old and new, including one of Tuesday’s eyebrows, going by the name Soot, enters Tuesday’s Treasure Tower and the final showdown commences.
This another brilliant story by Garth Nix, and, if possible, is better than Mister Monday, but I’m afraid the series so far doesn’t quite beat the standard set by Nix in his Old Kingdom Series.