"Foundation and Earth" by Isaac Asimov

  This is the last book of the foundation series, timeline-wise, although not the last one written, as Asimov wrote two prequels after this volume, which tie the Foundation series even more tightly into the Robot series, to the level that Hari Seldon's wife was a robot.  It is basically a continuation of the same story from the previous book,  where the exiled counsellor, Golan Trevize, is trying to figure out if he made the right decision when he gave his nod to Gaia and eventually to Galaxia (in the previous volume "Foundation's Edge"), and withdrew it from both the Foundation and the Second Foundation, leaving their leaders furious.  Trevize now embarks on galaxy-wide search for Earth, the mythical 'origin' planet of the entire human race, now populating the entire galaxy.  He finds that every reference to Earth is carefully deleted from any and all record keeping systems of the known universe, but then he discovers the "Spacer" worlds and coordinates for three of them.

  In this way Asimov ties the Foundation series with his Robot series, which is in a much closer future alternate universe, and originally was unconnected.  He further completes that tie when in the last chapter of the book reveals that the secretive 'man in the shadow' was no one else but Daneel Olivaw, the most famous protagonist of Asimov's 'Robot' stories.   On the three Spacer world they visit, the crew is always exposed to danger which is usually only escaped by the 'deus-ex-machinae' device of 'Bliss' the representative of Gaia on the ship, who is also accidentally a very sexy woman, in a physical relationship with the third crew member J. Pelorath, a mythologist.

  The book is less of a character-based novel than a barely-disguised scientific discourse in futurism of the highest sort, about the future of the entire human race, and it shows in cold logic that this is the only viable way of long-term (and long-term here meaning millions, even billions of years) survival for the entire race and life in general, in a case where the human race is the only sentient race in the galaxy, even in the universe, though the other galaxies are irrelevant in Asimov's fiction.  At moments the book reads very slow, as the flow is adulterated by huge tracts of non-sequitur monologues, and there is not much of the character drama for which the atmosphere of the original Foundation Trilogy was famous.  Both this and the previous volume won awards, don't get me wrong, but this might have been more like tribute to Asimov's universe, than to the readability of the tomes at hand. Ultimately, a great conclusion and tie-in with Asimov's other series, but definitely not for the beginner in Asimov's universe.