The central conundrum this novel explores is the dichotomy between safety and liberty. At first glance they seem to be mutually exclusive, an inevitable trade-off between one and the other, but is it conceivable that they might ever be reconciled, for humanity to achieve both completely?
Humanity has spread out across the galaxy but now someone has unleashed a race of supremely powerful robots who's prime directive is to protect all humanity from harm. The are going from planet to planet imposing safety and happiness on all humans they find, whether they like it or not. All potentially harmful physical or intellectual activities are proscribed and if they're not happy, they are sedated with drugs.
There is a bewildering array of psudo sciences explored in this novel too. Not only were these robots made possible by the discovery of a new rhodo-magnetic spectrum of energy but also faster than light travel and bombs exponentially more powerful than conventional nuclear weapons. Some humans have stumbled upon discovering parapsychological powers which they are using to resist the robotic occupation and these seem to be the unconscious manipulation of yet another spectrum of energy; the psychophysical. Could these three types of energies be related in some way to form some grand unifying theory of everything including consciousness itself?
So, this is an action packed novel that is also packed with ideas and revolving around the central question of liberty verses safety. And like all great stories, it doesn't attempt to tell you the answer.