A satisfyingly baroque plot and strong action sequences make up for a lack of character development and moral complexity in this gory space opera from British SF author Asher. Human beings have considerable freedom in Polity Space, a mostly civilized place, but enormously powerful AIs make all the important decisions. Three monstrous creatures threaten the Polity: Dragon, a gigantic being of unknown origin; Skellor, an evil, once human scientist transformed by the nanotechnology of the extinct Jain race; and Mr. Crane, the monstrous killing machine who does Skellor's bidding. Aided by several AIs, supercompetent Earth Central Security agent Ian Cormac must deal with all these dangers before civilization is plunged into chaos. Unbeknownst to him, however, several powerful AIs are plotting to gain Jain technology, even if it means the destruction of the human race. This violent, fast-moving novel is lots of fun, but makes no concessions to readers unfamiliar with Gridlinked and Line of Polity, the earlier books in the series. (Jan.)