London. A snowy December, 1888. Sherlock Holmes, 34, is languishing and back on cocaine after a disastrous Ripper investigation. Watson can neither comfort nor rouse his friend - until a strangely encoded letter arrives from Paris. Mlle La Victoire, a beautiful French cabaret star writes that her illegitimate son by an English lord has disappeared, and she has been attacked in the streets of Montmartre. Racing to...