What an amazing series. (I'd use a number of exclamation points to emphasize this statement, but it might undermine my enthusiastic endorsement.) Farthing starts out as a cozy mystery in a British country setting, but it turns into a action book about power hungry facists.
It's set in an alternate 1949--a 1949 where the Brits made peace with Hitler in 1940 and the U.S. never got involved in WWII. In all three books, the chapters alternate viewpoint between the first-person narrative of a young woman (a different one for each book and each integral to the plot) and a third-person narrative of Detective Carmichael of the New Scotland Yard.
The genre blending of the mystery format and alternate history timeline is really well done. Walton's world is expertly built, giving enough information to be plausible, without overwrought details.
Ostensibly mysteries, Farthing and the other books draw you in with ever increasing stakes--and the stakes are really high. How fast could Britain slide into facism with influential pols pulling the strings? What can one person do to stop it? How much and who would you risk to ruin the plans of those seeking to take control?
Just like in Walton's Among Others, her primary characters are entirely relatable, even if you really have nothing in common. The personableness of their thoughts, worries, and interests bring the reader right into the story. And her villains are ruthless in a way that make Voldemort kind of tame. Lady Eversley beats out Mommie Dearest any day (and gives me the shudders months after reading Farthing).
I finished Half a Crown a couple of weeks back and am still going back to it, thinking over the story. Walton ties all three books together really well at the end. And, without giving too much away, at the end of the last one, I cheered with my hands in the air and tears in my eyes. The books were that good.
A new trade paperback edition of Farthing is due out soon. I highly recommend you get it.