A synthetic guardian from space teams up with a 6th-century Delaware Indian and a 20th-century high-school girl. Hahn Ixpodsix (Humanoid Android for Hyperspace Navigation class 9, ship 6) is an agent of an intergalactic EPA bent on preserving planets for the original inhabitants. He is shot down by a renegade HAHN just as he finds Earth; to escape immolating Manhattan, he jumps back 1451 years, thus entering his crash in the legends of a local Indian village. Fourteen Indian years later (just four hours to Hahn), the Indian boy born at the moment of his crash is sent on a vigil requiring Hahn to rescue him,'but the boy--Sky-Fire-Trail--steals a time-travel crystal and lands in Manhattan in 1990, just in time to meet Frankie, a 16-year-old girl. The three of them dodge through space and time to escape bad-HAHN, finally destroying him and helping Sky-Fire-Trail lead his tribe to new land to the north. There's everything--including a scene with a kitchen sink--here: ecology, artificial intelligence, genes as destiny, space opera, history, anthropology, coming-of-age, young love, bigotry, cultural erosion, and more. With so much going on, it is to Chetwin's credit that Hahn and Frankie emerge as credible characters; and while the technology may be mostly hocus-pocus, the anthropology rings true. The teeming mixture may not be to everyone's taste, but most will find it at least interesting.