The second volume in the classic hard sci-fi series by the renowned physicist and Nebula Award–winning author: "So good it hurts" ( Washington Post Book World ). 2076. Technology has propelled the world into a new age of enlightenment. Nigel has left Earth to explore space and search for alien life. But while on this captivating mission, humanity's birthplace has fallen prey to attack and its seas are seeded with alien lifeforms. Now, Nigel is left to search for the only savior he knows—the one who saved him once before—the alien machine called the "Snark." Having left the solar system and turned traitor to its alien masters, Nigel is unsure of the Snark's new allegiance. Is the Snark a friend? Or will it also turn on Nigel . . . proving to be a deadly foe?