When I was growing up, I loved books that mentioned Cumbria, especially if Carlisle was in there too, no matter how briefly, because it was so unusual to find anything literary to do with my sleepy little home town.
Now I live in London I don't have that problem, and instead have become fascinated by London's history, and books that mention areas I know particularly well.
So this book's a bit of a double whammy for me, because not only does it go into the mists and murk of the Victorian capital, but it focuses on the line I spent a good 18 months commuting on a couple of years back.
I can safely say it's not much more salubrious now ;)

Inspector Decimus Webb is unusual for a policeman in a crime novel in that he seems quite normal - his only real eccentricity is his reliance on his velocipede.
And whereas in most murder mysteries it's obvious whodunnit from fairly early on, there are a good few strong suspects here, all of whom get a good outing.

Finally, did you know that Baker Street station, so important in this novel, has a whole river flowing through it? The engineers very cleverly designed a system of pipes to allow the sunken river to continue on its way without hindering the progress of commuters and tourists (at rush hour, parallels with the Styx would be hard to avoid). So next time you're standing on the platforms for the Metropolitan, Circle or Hammersmith Lines and you think you hear a neighbour's tummy gurgle, think again...

Sent to BBC Radio Shropshire's OBCZ by minx2012, and nabbed by me because it looks interesting! And I want to find out if my instinctive reaction - "I'll read anything recommended by someone called minx2012!" - holds good.