1893. Dr Watson, still in mourning for the death of his great friend Sherlock Holmes, is now triply bereaved, with his wife Mary's death in childbirth. Then a telegram from Melbourne, Australia intrudes into his grief. “Come at once if convenient." Both suspicious and desperate to believe that Holmes may not, after all, be dead, Watson goes as immediately as the sea voyage will allow. Soon Holmes and Watson are together again, on an adventure through Bohemian Melbourne and rural Victoria, following a series of murders linked by a repulsive red leech and one of Moriarty’s lieutenants.