I enjoyed this book. Very good flow.
I decided to read it after watching and looking up background for the movie, Idiocracy. The movie was not the greatest, but it was very funny in some parts, and a little weird elsewhere. The basic premise to this movie and the book reviewed here is that smart people have fewer children than dumb people which has bad consequences after a while; loss of genes - sometimes important ones - over time is at play as well.
The main character (Ross) lives on Halsey's Planet which is far from Earth. Ross is a descendant of humans who were sent out to settle new worlds such as Halsey's.
A problem has developed in that Halsey's planet is losing population, but no reason is apparent. In addition, contact from other human settlements on other planets has dropped off.
One day, a ship from Earth arrives unexpectedly on Halsey's Planet. Aboard are descendants of the original passengers/crew - the ship took many many years to reach Halsey's given the great distance and lack of faster than light propulsion. The people on the ship are basically idiots, but they had a message to deliver - part of this message is a mathematical formula that no one understands.
This message leads to Ross going out to visit other worlds that humans had settled - he travels in a faster than light ship that has been well hidden since the settlement of Halsey's.
The first planet Ross travels to has been totally destroyed, so he moves on. The next planet he visits is tightly controlled by the oldest inhabitants; he meets Helena there and takes her with him when he leaves. The third planet he visits in ruled by women; things go wrong and Helena is sentenced to death and Ross and a guy (Bernie) who Ross met on this world are imprisoned in an orbiting prison. Helena escapes death and rescues Ross and their new friend, Bernie.
The next planet they visit is controlled by people who all look alike - the Joneses. Ross meets a doctor who performs plastic surgery on people who aren't Joneses to look like a Jones so that they can enjoy a better life. The dialog here gets a bit weird, since the Joneses use the word Jones in many ways when communicating. These people are also obsessed with the mathematical formula mentioned above. A really odd thing here is that Ross thought he was headed for Earth, but ended up on Jones world. There is a town named Earth on this planet which Ross visits to get information.
The Jones doctor then becomes part of the group and after Ross finds out what went wrong in navigation, the group heads toward the planet Earth. On Earth, the people are mostly good looking, but stupid, and they spend most of their time partying. Despite this, the planet is highly developed and safe.
After a very strange visit to a TV show, Ross soon finds a very unlikely person who leads him to the truth about who is really running things on Earth. The people running things explain to Ross what the problem is for all the human settlements and tells him how it can be fixed. The book wraps with Ross and his group returning to Halsey's.
The book is kind of funny in places and interesting in many ways. One caveat to feminists. The book was written in the 1950's and contains some sexist passages - but these are also balanced out in part; usually the effect is kind of comical.
Give it a try if it sounds like your thing.