I'm not going to go into all the details, because there are gazillions of fantastic reviews out there for this book. All I say is READ IT. This is an absolute feast for your imagination.
The Night Circus is carefully crafted in such a way that every little detail enhances the experience - the colours, the smells and the taste of all the treats you buy as a visitor of the circus...
I have never read anything like that. This book can not be rushed, it needs to be savoured bit by bit. All of the multiple characters are rich and vivid, - Celia and Marco, the sisters, Tsukiko, Bailey, The Reveurs, Widget and Poppet, Chandresh... They all come together like pieces of a puzzle, and it's breathtakingly beautiful.
This book is much more than the story of love. The love is a consequence of creating The Night Circus, which is absolutely magical.
I can't recommend it high enough.