The year: 2990 AD. The centuries old conflict between the hi-tech underground world of the Trackers and the primitive, surface dwelling Mutes continues with unabated ferocity. Steve Brickman, a Tracker wingman whose heart and mind is torn between the two cultures, embarks on his most dangerous mission yet: the rescue of Cadillac and Clearwater, two gifted Plainfolk Mutes held captive by the mysterious Iron Masters. It is a nightmare journey into the unknown but, once again, a shadowy presence guides Steve's footsteps and endows him with superhuman speed and strength in moments of mortal danger...

Patrick Tilley does it again in this book. Managing to sew together three recognisable cultures into a thrilling story of intrigue, action and adventure which draws the reader on effortlessly into wanting to follow the heroes and heroines of these stories.

Mr Snow, Cadillac, Clearwater and the rest of the Plainfolk Mutes bear an uncanny resemblance to the American Indians of the 18th century; Steve Brickman, Roz and the First Family are all unmistakeably modern American. The Iron Masters though, are quite scarily old style Japanese, with their roots in the samurai culture.

To bring these three cultures together in a story which not only reads well but hangs together is no mean feat, but its one which Tilley has managed to do without dropping the ball once.

I have already said I like this series. The more I read it again though, the more I am convinced that this is one of the great Science Fiction series of the late 20th century.