Warning: This episode contains spoilers for Episode One of Magpie Murders.

Anthony Horowitz has written dozen of books and scores of television dramas in his lengthy career, but the task of transforming his meta mystery novel, Magpie Murders — a crime novel about writing and publishing crime novels — was especially tricky. Fortunately for MASTERPIECE viewers, the resulting series is a delight, and the author explains the tricky choices he made to bring Susan Ryeland and Atticus Pünd to the screen.