Candace Millard wrote a thoroughly researched, yet exciting, narrative nonfiction which is quite the adventure! The source of the Nile River was a mystery in 1850 until two British men were determined to discover the answer. Speke and Burton were highly invested, intelligent explorers who clashed during their expeditions. Burton was a highly skilled linguist who spoke 25 languages and translated the Kama sutra into English. Good but long!