The Adventure of the Peerless Peer

The "Peerless Peer" of the title is none other than Lord Greystroke, the jungle-born scion of a noble English family, a duke in Britain, but in his larger estate of Central Africa, a king. The time is 1916, at the height of the Great War. The foreign office learns that a deadly formula has been stolen from the allies by Sherlock Holmes's old foe, the German agent, Von Bork. Sherlock Holmes & Watson are called to travel to Africa to retrieve the formula.