In 1891, the British public was horrified to learn that Sherlock Holmes had perished in a deadly struggle with the archcriminal Professor Moriarty at the Reichenbach Falls. Then, to its amazement, he reappeared two years later, informing a stunned Watson, 'I traveled for two years in Tibet, therefore, and amused myself by visiting Lhasa.'

Nothing has been known of those missing years until Jamyang Norbu's discovery, in a rusting tin dispatch box in Darjeeling, of a flat packet carefully wrapped in waxed paper and neatly tied with stout twine. When opened the packet revealed Huree Chunder Mookerjee's (Kipling's Bengali spy and scholar) own account of his travels with Sherlock Holmes.

Now for the first time, we learn of Holmes's brush with the Great Game and the world of Kim. We follow him north across the hot and duty plains of India to Simla, summer capital of the British Raj, and over the high passes to the vast emptiness of the Tibetan plateau. In the medieval splendor that is Lhasa, intrigue and black treachery stalk the shadows, and Sherlock Holmes confronts his greatest challenge.