The main character of this book is Pete Garden. Pete is part of a circle of California residents in a depopulated future world who own large swathes of property, and who regularly play a board game called simply the Game, at which they stake their property, and their marriages, and even their status as eligible game players. (Property owners are called Bindmen, and if you lose all your property, you are no longer a Bindman, and cannot play.) The Game is administered in part by the amorphous aliens from Titan, the vugs, who apparently put much stock in gambling. In addition, the wife-swapping encouraged by the game is intended to promote what is called luck: actually, interfertility. The human race is dwindling because a weapon developed during the last war made people largely sterile.

The book opens with Pete stumbling home after a binge -- it seems that he has lost his favourite property, Berkeley, and in so doing has also lost his wife Freya. But his personal concerns seem less important after he discovers that the man who won Berkeley from him sold it to a front for a notorious Bindman from the East Coast. Pete is also worried because he liked Freya, and he fears that his prospective new wife, on loan from another Game-playing group, will be less congenial. Moreover, he finds himself greatly attracted to a mysteriously fertile woman living in his remaining property, and also to her 18-year-old daughter.

Dick continues to throw idea upon idea, and to alter the direction the book seems to be taking. Some of the characters are PSIs (telepathy, precognition, and telekinesis figure prominently), and they resent the fact that they are not allowed in the Game (because they could use their powers to cheat). Then a murder happens, and Pete is implicated, along with several other members of his Game-playing group. And Pete becomes convinced that vugs have infiltrated the Earth. Then it turns out that there are multiple factions among the vugs... As you can see, there is a sense of kitchen-sinkery to this book, a sense that the author may have made it all up as he went along. Similar problems underlie the character relationships, which alter chapter by chapter. (I may have missed something, but I'm pretty sure one character is a vug some of the time, and a human at other times, not on purpose.) I don't think things really cohere.

Despite those problems, the book is readable and interesting. There are a number of nice minor touches, such as the artificially intelligent cars with attitude. And the character of Pete Garden, a fairly typical Dick protagonist, neurotic to the point of suicide attempts but basically decent, is nicely enough portrayed. It is by no means among Dick's best novels, but Dick is a sufficiently interesting writer that even his minor works are worth reading.