A Spy In The House, by Y. S. Lee

A Spy In The House, by Y. S. Lee
YA, 2010

Mary Quinn is saved from a hanging at age 12 by an innocent woman who offers her the chance to become something more. Now it's 1858, and at age 17, Mary is the newest spy for The Agency, a women-only group that solves mysteries of the day in a variety of situations.
Raspberry: An engaging premise, I was immediately reminded of a cross between The Magician's Ward, by Patricia Wrede (if you haven't read that series, do it NOW), and the Enola Holmes mysteries by Nancy Springer. The mystery is engaging, the romance sweet but not over-played, and the ending, while it leaves you hanging for the sequel, satisfying. At least for the present.
Fortunately the sequel, The Body at the Tower, is promised for August of this year, and I am anticipating running out to purchase it!
Graded an A-.

And a note on the cover - it's perfect. It's beautifully done anyways, but the girl on the cover looks very much the way you imagine her by the time you're finished reading.