Never-before-seen cases meticulously chronicled by Dr Watson are published for the first time. Crimes of intrigue and suspense: Marguerite Rossignol, the French Nightingale, is found backstage of the Cambridge music hall strangled with one of her own stockings; the British Prime Minister is sent a dead rat and a threatening letter; and a girl drugged on morphine is somehow linked to a Californian goldmine.
Across the lights of London and up to Scotland, Holmes and Watson encounter a Russian agent provocateur, the ghost of a woman who drowned in a boating accident and a blackmailer who calls himself the Pied Piper in their endeavor to solve this series of chilling mysteries.