The Thousand isn't typically a book I would have picked up to read. I don't tend to read thrillers and try to avoid anything involving math. But I happened to win a copy of the book in a contest on twitter (which I didn't know I entered). And because the book is set partially in Chicago and Guilfoile is a Chicago author I felt compelled to give it a shot. 
 I'm so glad I did because I found the story to be completely captivating. It's one of those books that as soon as you think you have figured something out... guess again. 
 The Thousand is a group of people who for generations have followed the teachings of Pythagoras. His teachings have to do with the relationship between numbers and the order of the universe. 
 Set in Chicago and Las Vegas, the book centers around a woman named Canada Gold. When Canada, or Nada as she is known to friends, was a child she received a neurostimulator implant in her brain as a last attempt to control her severe attention deficit/hyperactivity disorder. The neurostimulator or spider (as Nada called it) gave her special abilities. She notices things that people didn't see. She hears things that people didn't hear. She uses these abilities to her benefit in Las Vegas first counting cards and then as a private investigator. 
 Because she is so skilled she is hired by a businessman to return to Chicago and help him acquire art from an eclectic artist named Burning Patrick. Nada grew up in Chicago the daughter of a famed musician who was murdered shortly after he was acquitted for the murder of a young student. As the story progresses the reader finds that everything believed to be truth is really part of an elaborate scheme. And everything is connected. Both factions of The Thousand are looking for Nada and she doesn't know who she can trust. 
 As a life-long Chicagoan, I found Guilfoile's descriptions of the city to be gripping. He nails the descriptions of the people and the places. I found the scene involving the riot in the park to be particularly haunting. I also fell in love with some of the characters. I felt for Wayne Jennings, the head of security who loves Nada. I was sad for Nada's best friend, the prosecutor. Kloska, the veteran Chicago Police Officer, seemed like someone you want to hate but underneath it all there's something oddly appealing about him. He's looking for the truth even if it costs him everything. 
 The one problem I had with the book was that I had a hard time keeping track of the two waring groups, Acusmatici and the Mathematici. I had to keep thinking back to try and remember which group was which. But it didn't keep me from enjoying this story. In fact it probably helped enhanced the story since I couldn't quite remember which group was responsible for which activities. 
 I would definitely recommend this book to anyone looking for a good thriller. You won't regret it.