Hints of the direction he would have taken with Dune 7 are in Heretics of Dune and Chapterhouse: Dune; however,many unanswered questions remain. He did, however, tell author Norman Spinrad that he "'planned to end the series with a novel that would transition to a fictional universe of democratic rule." Brian and Kevin completed Dune 7 as two separate novels set immediately after Chapterhouse: Dune. They were released in 2006 and 2007, titled Hunters of Dune and Sandworms of Dune, respectively. The books received a mixed critical response.