The Three-Body Problem

Pros: Usually, the more you know about the underlying science, the less believable/engrossing a sci-fi book is. Three-Body Problem is that rare sci-fi book that is better if you know more of the science it engages with. As a physics guy, I loved that. It's also really clever in employing science concepts as plot devices; from the famous three-body problem you see early on, to the use of non-digital computing, to nano technology, everything feels authentic. Also, from my own experience in the sciences, I thought the way that Earth scientists dealt with anomalies was handled in exactly the right way. Also, the author's afterward is excellent.

Cons: pretty technical at times; I was a physics major and still had to Google a few things. Because it's translated, it's also a little clunky in places. Together, these can make a few chapters drag on a bit.