The book offers fascinating insights into both the history of radiobiology and the life of Hal. It contains much unique biographical material made available to the author over the past 35 years by Hal's contemporaries, many of whom have since died. Great influences on Hal's life and studies, including his unusual high school, Christ's Hospital, and his firm moral beliefs, are described. But his life was not merely a gentle, cloistered existence in academia. Its ups and downs included events that would not have been out of place in a Hollywood drama. The book, the first book-length biography of Hal, is intended for all who enjoy this genre (including those without a scientific background) or have an interest in the history of radiobiology and radiotherapy.