I was recommended this book by someone who described it as two stories in one - the history of a serial killer and the history of the Chicago World's Fair. This sounded great to me, as I love a nonfiction book that weaves things together. Unfortunately, this book felt less like weaving and more like patchwork - while the World's Fair did happen at the same time and place, they didn't seem to have much else to do with each other to validate the juxtaposition.

I am not a true crime person, so the parts of the book about H.H. Holmes were not so interesting to me, and didn't come off as feeling very mysterious.  It almost feels as if this was trying to get the interest of true crime fans, but the history of the fair is what really made this book worth reading. I did love the history of the World's Fair told by Larson, enough to still rate this book as 4 stars and say it's worth recommending. If a reader was seeking a thrilling true crime history and got an in depth history of the planning of the first World's Fair along with it, this book may fall flat. (Or perhaps, gain them a new interest if they're into it.) As someone more interested in the in depth history of the planning of the first World's Fair, I could have gone without the H.H. Holmes bits completely.