Once in a long while friendships develop among people and remain in force throughout their adult lives. The figures involved in that relationship share their personal, intellectual, and emotional feelings resulting that at times they appear as extensions of each other. What I have just described is probably a utopian relationship; however the subject matter of THE FIVE OF HEARTS by Patricia O’Toole comes closest to achieving that ideal. The book centers on the interactions between Henry and Clover Adams, John and Clara Hay, and Charles King from the end of the Gilded Age in the late 19th century through the death of Henry Adams near the end of World War I. In her warm and intimate portrait of her characters O’Toole explores all aspects of the interactions of these five individuals who created a salon like atmosphere naming themselves the “five of hearts.” Of the five individuals it is most likely that the reader is somewhat familiar with Henry Adams and John Hay. However, the study of their lives and their spouses along with Charles King provides a much more thorough analysis of late 19th and early 20th century culture and intellectual history than if the author concentrated on Adams and Hay alone. The author provides insights into the flaws of her subjects and their impact on each other, as well as the world they touched. Throughout the book the important figures of the time period ranging from Henry James to Theodore Roosevelt appear and O’Toole offers unique perspectives that are based on thorough research and strong analytical skills. If one is interested in gaining an understanding of the intellectual and personal lives of the Adams and Hay families and the life of Charles King and their important contribution to American history THE FIVE OF HEARTS makes for a wonderful read.