One of Isaac Asimov's SF masterpieces, this stand-alone novel is a monument of the flowering of SF in the twentieth century. It is widely regarded as Asimov's single best SF novel. Andrew Harlan is an Eternal, a member of the elite of the future. One of the few who live in Eternity, a location outside of place and time, Harlan's job is to create carefully controlled and enacted Reality Changes. These Changes are small, exactingly calculated shifts in the course of history, made for the benefit of humankind. Though each Change has been made for the greater good, there are also always costs. During one of his assignments, Harlan meets and falls in love with Noand#255;s Lambent, a woman who lives in real time and space. Then Harlan learns that Noand#255;s will cease to exist after the next Change, and he risks everything to sneak her into Eternity. Unfortunately, they are caught. Harlan's punishment? His next assignment: Kill the woman he loves before the paradox they have created results in the destruction of Eternity.

艾萨克•阿西莫夫 Isaac Asimov （1920 ~1992）

俄裔美籍作家，全知全能，被全世界读者誉为“神一样的人”。美国政府授予他“国家的资源和大自然的奇迹”这个独一无二的称号，以表彰他在“拓展人类想象力”上做出的杰出贡献。

阿西莫夫创作力丰沛，一生之中著作近500 本，涉及杜威图书分类法的每一个范畴，涵盖人类生活的每一个层面，上天下海、古往今来、从恐龙到亚原子到全宇宙无所不包，从通俗小说到罗马帝国史，从科普读物到远东千年历史，从圣经指南，到科学指南，到两性生活指南，每一部著作都朴实、严谨而又充满幽默风趣的格调。

作为人类世界里最伟大的科幻小说家之一，阿西莫夫曾获得代表着科幻界最高荣誉的雨果奖和星云终身成就“大师奖”。他于1955年完成了一部极富远见的、关于时间旅行的长篇小说《永恒的终结》，厘清了关于时间旅行的终极奥秘和恢宏构想。问世60年来，这部作品被全球科幻迷们一致奉为阿西莫夫的最高杰作。