Great for those who enjoy the gaslight era, and even more so if you'd enjoy reading about the statistics, minutia, architects, and logistics of building the Chicago Worlds Fair. Although I like the setting, I didn't find the details of the Fair nearly as interesting as the bits about the serial killer H.H. Holmes. Erik Larson apparently anticipated this and salted huge chunks of the book with short chapters about the murders. I didn't like this carrot-on-a-stick approach. Still, the book is well written and the amount of research Larson did is clearly prodigous. The last several chapters are also soley about Holmes, which helps satisfy the reader's drawn out hunger for that subject.