It's an invitation that will change everything...

It's 1923 and in a decade that promises excitement and liberation, Pearl Glenham and her father are invited to a mysterious country house party on the Dorset coast, by a total stranger.

Her father claims not to have any prior association with Highcliffe House, but upon arrival, it is apparent that he has a shared history with several of the guests, although he won't admit it. Belatedly discovering

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As a dense yellow fog swirls through the streets of London, a deep melancholy has descended on Sherlock Holmes, who sits in a cocaine-induced haze at 221B Baker Street. His mood is only lifted by a visit from a beautiful but distressed young woman-Mary Morstan, whose father vanished ten years before. Four years later she began to receive an exquisite gift every year: a large, lustrous pearl. Now she has had an intriguing invitation to meet her unknown...