September, 1925. After their recent adventures in Transylvania, Mary Russelland Sherlock Holmes look forward to spending time with Holmes' son, thefamous artist Damian Adler, and his family. But when they arrive at Damian'shouse in the French countryside, they discover that the Adlers have fled from amysterious threat.In the ominously empty house, Russell discovers four crates packed withmemorabilia related to the artist Horace Vernet, including an old journal writtenin a nearly impenetrable code. Intrigued, Russell sets about deciphering theintricate cryptograph. The secrets of the past appear to be reaching into thepresent. Could there be things about Holmes' ow n history that even themaster detective does not perceive?