Arthur Koestler
The structure of the book is unusual. Part One 1940-1951, has six chapters whose authors are Arthur Koestler and Cynthia Koestler, alternately. Part Two 1951-1956, also consists of six chapters, all by Cynthia Koestler, followed by an Epilogue written by Harold Harris, an Appendix by Arthur Koestler, and an Index.