A prequel to Eon (1985) and Bear's subsequent hard-sf yarns describing the Way, a multidimensional passage to other worlds and times. The Way is controlled by the Hexamon, whose preoccupation hitherto has been fending off incursions by hostile alien Jarts. A newly discovered planet, Lamarckia, is home to marvelous life-forms called "ecoi"; each single "ecos" is composed of bizarre plant/animal hybrids known as "scions" analogous to single cells, all of them managed, so it is hypothesized, by a "seed-mistress." But then radical fanatic Jaime Carr Lenk opens an illegal Way gate and disappears onto Lamarckia with 4000 followers. The Hexamon dispatches agent Olmy to investigate. Arriving 37 years later, thanks to the uncertainties of Way transit, Olmy discovers a brutal war in progress between Lenk loyalists and rebellious Brionists. In order to better inspect the ecoi, Olmy joins the crew of an oceangoing research vessel. They come upon a dead ecos, confirm the seed-mistress hypothesis, and discover the skeletal remains of quasihuman scions. Later, Olmy barely survives shipwreck in a gigantic storm whose living components comprise yet another ecos. Finally, coming to the stronghold of the rebels and their bloodthirsty leader, General Beys, Olmy must somehow compel Brion, Beys, and Lenk to face the truth about their presence on the planet. A remarkable and utterly convincing feat of creation, from which the lack of really memorable characters and their often turbid motivations detracts hardly at all.