Andrew Harlan is an Eternal, a man whose job it is to range through past and present Centuries, monitoring and, where necessary, altering Time's myriad cause-and-effect relationships. But when Harlan meets and falls for a non-Eternal woman, he seeks to use the awesome powers and techniques of the Eternals to twist time for his own purposes, so that he and his love can survive together.

by Isaac Asimov, Robert SilverbergIn a twenty-first century Earth where the development of the positronic brain has revolutionized the way of life, beloved household robot ""Andrew"" struggles with his unusual capacity for emotion and dreams of becoming human. Reprint.

Asimov's Mysteries, published in 1968, is a collection of 14 short stories by Isaac Asimov, all of them science fiction mysteries. The stories were all originally published in magazines between 1954 and 1967. Four stories in the collection feature the character of Wendell Urth, who is a leading extra-terrologist. Urth is eccentric in that he has a phobia of all mechanical forms of transport. Physically Urth resembles Norbert Wiener. He appears in the stories when he is consulted by an agent of the Terrestrial Bureau of Investigation, H. Seton Davenport, in cases which have him baffled - a parallel with the way in which Inspector Lestrade consults Sherlock Holmes. In a fifth story in the collection, The Dust of Death, Asimov shows Davenport a generosity that Conan Doyle never extended to Lestrade in demonstrating the former's ability to solve a case for himself without outside assistance.