Mister Monday (Keys to the Kingdom Series #1)

Best-selling author Garth Nix creates a magical world and an intriguing mystery in this new blockbuster series.

Seven days. Seven keys. Seven virtues. Seven sins. One mysterious house is the doorway to a very mysterious world -- where one boy is about to venture and unlock a number of fantastical secrets.
This is another thrilling, triumphantly imaginative series from Garth Nix, the best-selling author of THE SEVENTH TOWER, SABRIEL, and LIRAEL.