Sherlock Holmes and the Hapsburg tiara

"[I]n London, in the middle of the night. Holmes and Watson are summoned to a crime scene that, not so familiarly, seems to vanish before their eyes, as they find themselves with neither evidence nor a client. They do not want for opposition, however; not for long, not with the governments of three great empires arrayed against them. As Holmes strives to unmask his most cunning, ruthless, and elusive foe, he is transported into a world of high finance rife with intrigue and crime. With a cast of characters that includes the enchanting lady of fortune Countess D'Espinau and historical greats like Winston Churchill and Cecil Rhodes as well as a poorest-of-the-poor beggar girl whom Watson adopts, Holmes follows a trail that leads ultimately and unpredictably to the fabled and fabulous lost Hapsburg tiara."--Publisher's description.