In the follow-up publication to the successful and award-winning Secret Notebooks of Agatha Christie, expert and archivist of the work of the queen of detective stories John Curran takes us through six decades of her writing career. Among other things, she describes how the publisher persuaded her to change the ending of her first detective novel The Mystery of Styles Castle (in this book you have the opportunity to read the original resolution of the novel for the very first time), how she prepared in the 1940s to get rid of Hercule Poirot, or what topics she was thinking about at the end of her life, but she did not have time to realize them. Among other things, two hitherto unknown short stories from her legacy are also presented here - The Man Who Knew and the working version of The Case of the Housekeeper with Miss Marple.