This story of a highly intelligent observer of the turbulent 20th century who was intimately involved as the secretary and bodyguard to Leon Trotsky is based on extensive interviews with the subject, Jean van Heijenoort, and his family, friends, and colleagues. The author has captured the personal drama and the professional life of her protagonist--ranging from the political passion of a young intellectual to the scientific and historic work in the most abstract and yet philosophically important area of logic--in a very readable narrative.