This book is considered the first of Brin's first Uplift Trilogy, but it is really a stand-alone novel, set far apart in setting, plot, and style from _Startide Rising_ and the _Uplift War_. That said, it is in this book that Brin first introduces the readers to the universe that will be developed more fully in his later works-- and what a fascinating universe it is! Humans 'uplifting' dolphins and chimps to a sapience equal to our own, religious/intellectual/political conflict on earth between those who believe that humanity evolved and those who believe that an alien race uplifted us long ago only to abandon us, a vaguely unsettling futuristic social structure where humans are divided into full citizens with rights and 'probationers' without, and of course, a billion-year-old shared culture of galactic races into which earth's young, self-taught, human culture seems to have rudely and unpreparedly been thrust. It's great stuff... but the problem here is the story. What starts off as a kind of sci-fi quest to fly on a 'sunship' into the sun to see if the 'ghosts' that have been reported there might be the lost patron aliens who once uplifted humanity evolves into a murder/sabatoge mystery. That's fine by me, but the 'whodunnit' part of the mystery just doesn't work very well in my book. For the most part, it seems rather convoluted involving aspects of sci-fi physics and alien politics that the reader is not sufficiently introduced to in advance. Even worse is the fact that the entire novel is told from the perspective of a single protagonist-- except for one chapter early on-- in which the reader witnesses a conversation that... well, it doesn't really reveal the *whole* of the whodunnit part of the mystery per se, but it gives you too good of an idea of at least one of the key figures involved. That just strikes me as a storytelling mistake that ought to have been avoided. All in all, this is a decent book, but it's more interesting for the ideas that will come to full bloom in Brin's later uplift books, than for the story itself.