The events of Dune were a tentative step towards the superhuman. Paul Muad'Dib was the Messiah, gifted with prescient powers, trained to a razors edge, and rising from renegade ducal heir to conqueror of a galaxy. But his visions revealed something terrifying, something which lead to his defeat in Dune Messiah, and a dangerous pathway.

Children of Dune is a return to Dune, in a way that is both more rewarding than Messiah, but also a reflection of the initial book. Young Leto II Atreides has to find his own path, against the conspiracies of his Aunt, St. Alia of the Knife. Alia's regency has become corrupt and calcified, and Alia herself fallen into possession by an ancestor, a state both the Fremen and Bene Gesserit deem 'abomination', and correctly so, since her possessor is the Baron Harkonnen.

Whereas Dune was obsessed with the future, with the power of Paul's visions and the potential of the Fremen, Children is haunted by the past, most directly by the genetic ancestral ghosts that Leto, Alia, and Leto's twin sister Ghanima have access to. These genetic memories are a wellspring of experience, and a threat.

Leto escapes an assassination plot, and thought dead, falls in with the outcast Fremen of Jacurutu, reviled as ancestral water stealers. There he is tested with massive amounts of spice, confronts the mysterious Preacher, a charismatic blind prophet who rails against the deification of Muad'Dib, and embarks on the start of his Golden Path. Leto merges with the sandtrout, becoming a hybrid human sandworm. He will rule for thousands of years, a force which will make humanity evolve.

As a kid, I really loved the weird ambition of this book, and the fantasy of Leto's sandworm power armor. As an adult, well, it's Dune with more weird bits.