On a fine October afternoon in 1882, Rose Donnelly, maid-of-all-work, disguises herself as a boy in order to follow the callow, yet brilliantly determined Sherlock Holmes in his pursuit of a thief. Through narrow alleyways and cobbled lanes wedged between Whitechapel, Bethnal Green and the broad back of the City, she's led into deeper territory - worlds he knows well. So well, in fact, that he nearly has her collared on her first time out. Still, Rose learns he has a bolt hole somewhere in Spitalfields. He speaks a smattering of Yiddish. He has a talent for picking pockets. He's a genius with the deceptively simple disguise. It's a thrilling start. It's for her doctoral thesis. Or so she believes. This is the fifth original Faction Paradox novel.