The end of the story of the writing of The Lord of the Rings, including Tolkien's attempts to plot out the very end of the story - Gollum always had a role in the destruction of the Ring, but exactly what that was took some time to work out; but Saruman only gradually emerged as the villain in The Scouring of the Shire, and a postscript of Sam and Rose and their children twenty years on was dropped on the advice of Tolkien's beta readers (I wonder if whether J.K. Rowling was given the same advice about the end of the Harry Potter series; if so, she ignored it).

The book also includes drafts of an unpublished novel called The Notion Club Papers, written in the mid-1940s, in which a club of academics - in 1987! - listens to one of their number who has uncovered, through his dreams, another variation on the story of Eärendil and the fall of Númenor which was one of the earliest elements of Tolkien's mythos and which he never quite got right. What's interesting about The Notion Club Papers is that it clarifies the reason for part of the failure: the characterisation is all in the framing narrative, and the epic mythos all in the Númenor bits without really much in the way of interesting personal glimpses. What Tolkine managed in The Hobbit and particularly in The Lord of the Rings was to unite the epic and the personal, but it was only after long years of effort and rewriting, and I don't think either half of The Notion Papers was really salvageable. Still, it's interesting to map the roads not travelled.