When it comes to communal behavior, Russell has often observed that there are many kinds of madness. And before this case yields its shattering solution, she'll come into dangerous contact with a fair number of them. From suicides at Stonehenge to a bizarre religious cult, from the demimonde of the Cafe Royal at the heart of Bohemian London to the dark secrets of a young woman's past on the streets of Shanghai, Russell will find herself on the trail of a killer more dangerous than any she's ever faced--a killer Sherlock Holmes himself may be protecting for reasons near and dear to his heart.