_Superintelligence: Paths, Dangers, Strategies_
This is the best single source for the memes about AI turning the universe into paperclips.
Sadly, if you've already read a bunch of LessWrong, this does not have better arguments, just a different flavor of narrator.
_Avatar: The Way Of Water_
Pretty good, especially in IMAX. (3d effects are meh.)
The evil humans have switch from evil mining to evil whaling and evil colonization.
Was worth the $20, anyway.