A mission to retrieve the spaceship Discovery finds life on Europa and an active monolith.

I had a hard time getting into this book because the jarring differences between its account of events and what was written in the preceding book.  But, because the movie was slightly different, and there have been discoveries since 2001 came out, I guess that was inevitable.  There were also some excruciatingly slow sequences, notably all including Bowman -the main character from the last book, and especially when he's "observing" life on Europa and in Jupiter.  But there were brilliant moments, as well, such as the excellent chemistry between crew members, and the revelations about the aliens' intentions.  That a new sun would be created to create a new intelligence, and not for human purposes, must be quite a blow to morale!