I've known a few people who really like Eloisa James. There's a couple authors that I read, that read Eloisa James' books, and highly recommend them. However, this is the first book by her that I've read. Once I read the premise and that it was loosely based on the Ugly Duckling I was even more interested. I like the whole "ugly duckling turning into a swan" type story. I think it's something that we all can relate to. Everyone, at some point, feels insecure about themselves and some attribute they have and it's the way they overcome the insecurity that is really interesting. Whether it's something that changes within themselves or an outside force. The story of the ugly duckling is one commonly used in writing. 
 Eloisa James does a great job with the story because it's not it's sol focus. The transformation of Theo from duckling into swan is not all the book is about, but it takes the idea of this less-than-beautiful girl and spreads out from there. 
 This story is about James and Theodora (Theo) who have basically grown up together as brother and sister (although they aren't related by any means). James has always been considered quite handsome and someday he will become a Duke which makes him even more attractive to many women. Theo on the other hand has always been considered plain and unpretty. Some even go so far as to suggest that she is really a boy since her figure leaves something to be desired. So it is confounding to everyone as to why James would marry Theo. Theo herself wonders why James has suddenly taken an interest in her, but when she really thinks about it she realizes she in fact really does love James herself and is happy. When the surprising reasons for the marriage come to light James leaves, which causes everyone to assume he finally saw Theo for the "Ugly Duchess" she was and couldn't stand to be married to her any longer. 
 What comes about next is the two young adults changing and growing into the adults they will be. The experience changes both of their lives and they both have to learn to live with what happened in their marriage. Will James ever return, and will they ever be able to resolve the conflict? 
 THe book spans a number of years through which our hero and heroine go through a lot of changes. I don't typically like it when it takes a good number of years for our HEA, but our characters had a lot of growing up to do. They start out the book at 17 and 19 respectively and regardless of the times (1809) they were still young. So I think that the amount of separation was needed. The only problem that this caused was the split focus between both James and Theo. For me the book switched back and forth so much that when I would get into what was happening in one of their lives it would switch and throw me off. Then I would get invested in the other, and it would switch back. 
 I will say that the book resolves itself in true romance fashion. I may have to check out other titles by Eloisa James. If your looking for a quick, light read with a good HEA then this is a good place to start.