I just read Humans, the second novel in The Neanderthal Parallax trilogy by Robert J. Sawyer. It was just the thing to pass the time flying back from Houston, Texas with a few hours to kill in airports and on airplanes. A few months ago I read Hominids, the first novel in the trilogy.
I won't spoil it for you by revealing any details, but the trilogy is about making contact with a version of Earth in an alternate universe in which Neanderthals, rather than humans, became the dominant species.
Sawyer did his homework when it came to Neanderthals. There is increasing evidence, some of it published since his novel was published, that Neanderthals may have been as intelligent as humans. Sawyer's insight into their possible religious beliefs is an extrapolation based on real evidence from fossils and artifacts. Their possible speech patterns is also backed up by recent computer models based on Neanderthal skulls.
As usual, Sawyer gets in his Canadian content, with some of the action taking place in Canada and several important characters who are Canadian. It also has events taking place in the United States, including New York City and Washington, DC. There is a particularly moving scene at the Vietnam War memorial that Sawyer thinks was one of the best things he's ever written.
I found it a great read. If you are not an SF fan you will likely still enjoy this novel -- like all his books it's not so much about technology or aliens, but about believable characters, interesting situations, and thought-provoking questions. It also has an element of crime mystery too.
The ending was particularly exciting and had a interesting plot twist that caught me off guard.
I'm looking forward to shortly reading the final book in the trilogy, Hybrids.