Mr. Monday by Garth Nix

I gave this book four out of five stars. This novel is about a young boy named Arthur who is about to die from an asthma attack, but is saved by a man who gives him a mysterious key shaped like a minute hand on a clock. The man later wants the key back and goes to any means to get it-including creating an illness that sends Arthur’s town into Quarantine. At the same time he got the key he got a strange book that lead him to a house no one else can see. His only hope is to go into the house to discover the secrets of the key before people in his town start to die.

It's a very good book, but has a slow beginning. The beginning has the reader every bit as confused as the protagonist, but it clears up when Arthur enters the house, after that it’s very easy to follow.