The Keys to the Kingdom

The Keys to the Kingdom by Garth Nix is a gripping fantasy saga packed with magic, dangerous foes, and an epic battle for the fate of the world. The protagonist is Arthur Penhaligon, an ordinary boy who unexpectedly becomes a key player in the fight for control over a mysterious realm called the House. Each day of the week is ruled by a different magical entity, and Arthur must battle them to reclaim what was stolen – and perhaps save the entire universe.