
The second intriguing thing about the story is that the author is open about the fact that this all female spy agency, which takes in the untouchables of the London streets, free of charge, educates them, and sends them out to investigate the rich and powerful, is completely fanciful. Too often, period pieces write revisionist history, where everything is picturesque and the plot lines totally out of joint with the happenings and mores of the time. Lee takes as much of actual history as possible, and when she integrates the more fanciful and incongruous elements, makes it plausible.
Overall it was a fast-paced, well-developed, mystery that kept me guessing. The romantic entanglements didn't interfere too badly with the central plot, and the segue into the next two books of the trilogy was smoothly done. No complaints from me.