It is 1917 and the Great War has been raging for three long years. Mycroft Holmes grows suspicious of one of his agents in Constantinople. Naturally, he wants to send a man to investigate who knows the language, the people and has an exemplary war record, including fourteen months posing as a German officer in Berlin. But Sherlock Holmes proves to be, for once, stubbornly unwilling to fulfill his older brother's request. When Mycroft is shot and left for dead, Holmes is forced to Constantinople to uncover the man behind the deed. Unfortunately, before he was assaulted Mycroft failed to...