Out of all of the Dune books, Heretics of Dune feels the most like pulp sci-fi. That is not to say that the prose is particularly unimaginative or the characters wooden, but there is something about it that reminds me of books bought in second hand shops whose titles I have long forgotten. It's really hard to get my thoughts down about Heretics; brilliant work of fiction it is not, but I still enjoy every read of it, nonetheless. The formula is very different to that of the previous books, mostly gone is the fascinating ecology and philosophy, but in their place is perhaps the strongest cast of characters since the first trilogy. There are moments when you have to question what Herbert was thinking, and others that are strangely poignant.
Heretics is the first book to be set largely away from Arrakis. Once again, the timeline has jumped forward over a thousand years, and once again a ghola of Duncan Idaho is one of the main characters; this time being raised by the Sisterhood on the plant Gammu (was Giedi Prime) and in some way vital to one of their characteristic long schemes. As with all of the Dune novels, there's lots of politicking going on between the various factions, with an added dose of uncertainty introduced by new cultures returning from the scattering.
The choice of setting once again lets Herbert play with the sense of history present in the Dune universe. The God Emperor Leto II is now long dead, but, when Idaho is eventually forced to flee the Bene Gesserit keep with a few companions, he also encounters traces of the Harkonnen culture on Giedi Prime that trace back to the first novel and the time of Muad'Dib. It's a really interesting juxtaposition of time periods that gives a strange sense of double-vision: the events of all the previous books are layered together in such a way that God Emperor of Dune is seen as being in the distant past, but also somehow as part of the future to come. A hard thing to describe, but the closest I have felt to 'real world' history and mixing of cultures in a novel. That is further reinforced by the sections of the book that take place back on Rakis. Dune has now completed the cycle of transformation from desert world to paradise, and back again to desert world, but the culture is a strange mix of all of its previous incarnations.
The other highlight of the book for me was the characters. The Bashar Miles Teg was a particular highlight; as an Atreides in the very traditional sense, he felt very much like the Duke Leto I and is perhaps the most likeable character since the first book. Sheeana, an orphaned Fremen who can control the sandworms, was also very memorable and feels more human than many of Herbert's characters.
Alongside the good, there are plenty of rough patches. There's rather too much obsession with sex, especially as the culture of the Honoured Matres is introduced, and following all the various plot points can become difficult at times. I still enjoyed the book, however, and the ending still managed to take me by surprise, despite multiple read throughs over the years.
