The latest installment of Discworld lore (The Globe, 2015) from recently deceased speculative fiction legend Pratchett and coauthors Ian Stewart and Jack Cohen resumes the double-duty prose experiment of following the fate of Roundworld, aka Earth, in one stream of chapters while providing a nonfiction scientific commentary on "the evolution of evolutionary theory" in another stream. The narrative thread finds the wizards of Unseen University lamenting the inexplicable wrong turn Earth's history has taken with Charles Darwin's publication of Theology of Species, which poses the theory of divine creation (in a parody of contemporary intelligent design). Unfortunately, Victorian England's support of the work leads to a sudden slowdown in scientific progress that, without wizardly intervention, will result in humanity's destruction in the already forecast Big Freeze. In the alternating discussion thread, Stewart and Cohen recount the true origins and repercussions of Darwin's revolutionary natural selection hypothesis. For Pratchett fans saddened by the author's passing, the book is a must-read swan song, whereas science buffs who don't mind the fanciful story line will find the nonfiction essay chapters fascinating.