Frederica makes a delightful heroine because her views are strong in wanting to be an equal to men but not radically so (at least in today's standards). She seemed rational compared to Felicity, her younger sister. Lord Harry Danger (Danger??) is not dangerous at all but a true gentleman in every way seeking to capture Frederica's heart by solving the mystery of who the "orphans" really are. That mystery is NOT solved in this book. Maybe it is solved in the sequel about Felicity which I hope to obtain.
I enjoyed this book and hope to find the prequel also. There are some escapades involving drunks, thugs and thieves which add a rather odd element but seemingly the only way to introduce a little adventure into the dull Waverly's lives. Other characters are introduced but they are not fully developed -- one is Harry's mother -- very strange woman who does not appear to have a good head on her shoulders due to the constant bullying of her late husband.
Oh well, take the book as it is -- a light read with some appealing people.