Nooks and Crannies by Jessica Lawson*

Tabitha Crum has spent her entire life trying to win her parents' affections.  They have very little time for her and relegate her to household chores while they attempt to advance their position in London society.  Tabitha is also friendless expect for Pemberly, her pet mouse.  To pass the lonesome hours, Tabitha emerges herself in detective stories.  Then one Friday she receives a sealed invitation.  The weekend that follows changes her entire life and outlook.
Perfect book for readers who like suspense, hidden passageways (my dream to find one!!),  and mysteries.
To be honest, I thought I had the ending figured out by the eighth chapter but there are so many more surprises in the book that I was still compelled to read it.
I also liked the quotes from Tabitha's detective novels that begin each chapter.  I found their tone and cleverness amusing.
*Highly recommend.
Warnings: selfish parents, abandonment, someone dies, a very cruel character and some gruesome descriptions of murder paintings (in my opinion)