I hold Huxley in such high regard- both for Brave New World, and for his series of lectures which broadly outline the "scientific dictatorship" his brother Julian spent a lifetime working on, at the behest of robberbarons and technocrats. For these reasons alone, I gave Ape and Essence a try, but I can't honestly recommend that you do the same.
Ape and Essence is the 1948 followup to Brave New World. "Followup" is a nice, ambiguous word to use, because it isn't a sequel to BNW, but the story could possibly be taking part in the same constructed world. Unfortunately, Ape and Essence isn't written to the standard of Brave New World. It's not as engaging, and it doesn't offer nearly as much depth of insight as to how the society it describes is supposed to work. A barebones summary is probably in order here, so let's just say the A&E takes place several decades after World War III. New Zealand was somehow spared in the conflict, but North America completely leveled. A ship from NZ touches down on the California coast and makes contact with the locals. Shananagans ensue, including ritual murder and a citywide free-for-all orgy.
There's a pretty standard "Road Warrior" vibe to it, which probably seemed pretty edgy and creative in 1948, but trust me: it's been done much better in other works since. The only interesting thing about the story is that it is a theocracy, with rigid observations which echo some of the "scientific dictatorship" ideas more deftly explored in Brave New World. The commonality between BNW and A&E is that both civilizations have evolved oppressive regimes which don't feel oppressive to the people living under them. There is some use of coercive force, but unlike, say, George Orwell's 1984, it is not necessary that this be widely applied... just reserved for the dissident outliers. The average citizen submits willingly to a system that he has been bred and conditioned to not only accept, but to love.
The bit about the apes is a mislead... they aren't necessary for the story, and I can't figure why Huxley felt they deserved mention in the title.
Two stars. Two frickin' stars for Aldous Huxley. That probably means it only really deserves one.