From the Tower of Darkness by Poke Runyon is an adventure novel set in Egypt and the Sudan in the closing years of the 19th century. The British Army is on the march to recapture Khartoum and defeat the Arab slave-raiding empire that controls the upper Nile—but French agents are plotting to smuggle modern arms to the tribesmen. The only man who can thwart this scheme is the intrepid British secret agent Captain Alan Vaughan, known as "Elan Pasha."...