Arrowood has a problem. It isn't the fact that his sister has returned. Nope. It isn't the fact that his wife left - his fault that. It isn't that the beer has gone off.
It is Sherlock Bloody Holmes.
Finlay's book is about the anti-Holmes and Watson. Not bad guys, no, but the ones who handle those cases that are not classy enough for Holmes. Along the way, Finlay also subtley digs at Watson's martial status.
Overall the book is good. The mystery is a bit wrapped up in a bow, if you know what I mean, but the characters are engaging, and Finlay nails the period. He also puts in commentary about Holmes, and quite frankly, I think he should get a bonus for the whole riff about Adler because honesty, after what Moffat did with her, I so needed that.