An Urchin of Means

Ringo Devereux knows far too much for a man of his times. There's no simple explanation for it that doesn't involve improbable conversations about the future, and Ringo's advanced understanding of three-phase generators and the secret histories of his city are not things he can discuss with the Victorian Londoners around him. Even his origins as an orphaned street thief are far too dangerous for a young gentleman of means to reveal.
An encounter with a ten-year-old pickpocket, and a luncheon with Oscar Wilde and Arthur Conan Doyle draw Ringo back into the shadows of his criminal past. A stolen gemstone, a suspicious pawnbroker, and a damning bundle of letters are mysteries that require Ringo's thief's instincts, his obscure facts, and the help of a little girl with the skills of deduction like his.
But are these crimes as random as they first appear? What do a covert affair and a blue carbuncle have in common? Ringo knows too much, but someone knows more, and the identity of a mysterious red-haired woman is perhaps the most diabolically complicated plot of them all.