Curious phenomenon of writing, whereby an author (generally sufficiently well-established on the merits and market value of their own work to be able to do so without suffering the accusation that they are running out of ideas) will produce a sequel, prequel, interquel, or, on unfortunate occasion, straight _retcon_ of another author's work, usually after said author's demise or, at least, retirement. Notable examples: -- Dune, by FrankHerbert, which has been given a number of prequels (dealing with the affairs of Houses Atreides and Harkonnen) by (Insert Author Here) and Brian Herbert, the original author's son. -- TheTimeMachine, by HGWells, to which the rather excellent sequel TheTimeShips has been fashioned by StephenBaxter. A notable example, since its narrative allows not only the *events* of TheTimeMachine to be crucial to its plot, but also the fact of the _book_'s existence. Possibly also based upon a number of shorts written by H.G. within the Time Machine's universe... _See also The Space Machine by Chris Priest._ -- Automated Alice by JeffNoon --Philip K. Dick is Dead Alas, by Michael Bishop, is effectively a sequel to all of Dick's novels and to Dick's life itself. Dick appears as a character (or several characters) throughout the novel. -- Someone did a sequel, reflecting new physics knowhow and especially quantum theory etc, to George Gamow's 'Mr Thompson', about the scatty chap who fills his daydreams with thought-experiments. Those who aren't ArtsStudent__s, write. -- The Foundation Novels, by IsaacAsimov, for which three authors, Gregory Benford, Greg Bear, and David Brin, have written "The Second Foundation Trilogy", set (apparently, to judge from "Foundation's Fear") as a series of interquels to "Forward the Foundation", Asimov's last novel. Although it's not quite the same, DoctorWho being a gestalt writing effort anyway, great and inglorious infamy may also be awarded to John Peel's "War of the Daleks", which pays tribute to the memory of Terry Nation by re-writing, retconning, and eventually entirely rejecting the plot of his last written contribution to the mythology. If the book were actually any _good_, or if Peel hadn't specifically stated his desire for it to be a tribute to Nation in the _dedication_, it wouldn't be so unfortunate. Tch!