The play attempts to capture the interaction between Copernicus and Johann Joachim Rheticus as the younger Rheticus persuades Copernicus to finish his manuscript and publish the astronomical discoveries he's made. When I first started reading, I was skeptical of how this imaginative but necessarily conjectural endeavor would work ... thankfully Sobel's a writer with enough talent to pull it off, although I'm thankful that her editor persuaded her to add the contextual material.
By bracketing the play with narrative chapters outlining Copernicus' life and career up to the arrival of Rheticus, and then of his decline following Rheticus' departure (along with the publication history of De revolutionibus and an examination of its reception), Sobel manages to add heft to the dramatic interlude at the center of the book, while still granting her own fictional creation pride of place.
