I know that I read this book shortly after I graduated from high school. I'm not sure I remembered much. I remembered about the engineering of humans, but I'm not sure I was "mature" enough to understand the consumerism and free sex and drugs aspect. Basically, if one can keep society in a steady circle of consuming goods, having sex, and taking mind-numbing drugs, one can create a safe, happy, and strife-free society. To deal with the problems of drudge work, the powers that be, create people of lesser intelligence in their baby factories, and then condition them very carefully so that they'll find happiness in being an elevator operator, or hod carrier, or tiller of the soil, or whatever. The few who don't fit in, get shipped off to a remote island.
One such person who doesn't quite fit in is Bernard Marx. He goes on a trip to New Mexico where he gets to visit a "savage" reservation. That is a reservation on which Native Americans live by their traditional methods, hunting, gathering, cultivating, bearing children live (i.e. are still viviparous). It all seems to strange, but then they find a young white man and his mother living on the reservation. Apparently, some 20 or so years previously, the woman, Linda, visited the reservation, and apparently, her birth control efforts had failed. She was left behind and bore a son, John. Neither Linda nor John had fit in with the Native Americans. For some reason, they were taken back to "civilization".
Linda immediately took up the drugging and spent her time in a state of psychedelic bliss. John, who had learned from the natives to embrace a more "spartan" lifestyle, one of self denial and strict moral behavior, was not able to drift into drugs, nor to fit in any better with the folks back in "civilization".
So, how did it all turn out? Well, read it and find out for yourself. I didn't really like this book much, but then I'm an elderly, repressed Calvinist, so the society as described would appall me.