Sherlock Holmes Yearns For A Challenge When Lady Diana Arrives, Pleading For His Help, Holding Herself Responsible For The Accidental Death Of A Blackmailer.her Predicament Enthrals Holmes Who Knows The Blackmailer To Be An Aide To Count Von Runstedt Whom He Believes To Be The Head Of A German Spy Ring. He And Watson Probe This Conspiracy And Are Plunged Into A Series Of Escapades Which Take Them All Over London And Beyond Involving Them In Burglary, Treason And Murder.holmes Obtains A Vital Document Needing Decoding And Acquires A Scrap Of Paper Indicating The Whereabouts Of Top Secret Government Documents Which Have Gone Missing, But This Too Needs Is Also A Tale Of Two Women, From Opposite Ends Of The Social Spectrum, Who Profoundly Influence The Course Of Events.set Against A Backdrop Of The Mounting Tension In International Affairs In The 1890s This Is One Of The Most Politically Sensitive Of Holmes's Cases.