Ubik

Ubik takes place in a very futuristic 1992, where everything from doors to appliances demand coins to perform their action. The principle character are employees of a "prudence" organization that have the ability to counteract psychic powers. The owner, Glen Runciter, communicates with his wife who resides in "half life", a post-death state that allows the dead to still communicate with the living. (However, communications gradually cause the half-life to fade.)

One day a new recruit is brought in that has a special "anti-precog" capability that allows her to go to "change" the past. She along with some of Runciter's best employees go on a mission to Luna which ends up being a trap. They find their world mysteriously regressing backwards. They also find strange communications from their boss showing up in odd places. They blame the new girl for this problems. However, they eventually discover it is another half-lifer that is "eating them". Luckily, some half-lifers have come up with a counter-measure, Ubik.

Like Dick's Flow My Tears the Policman Said, Ubik has an odd approach to "personalized" time travel. In Ubik, it initially appears somebody is purposely regressing people in the past until they whither away. However, it is later revealed that almost the entire world was created in somebody's mind, and that time period just happened to be a convenient one for them to be in.

The novel continues to build up interesting twists on existence itself, and eventually ends with a quasi-biblical quote. The "half-life" world has strong forces of good and evil that are trying to steer people to their side. They give messages and hints of the best course of action, and even occasionally try to assist. However, the end result is dependent on the will and actions of the half-lifers themselves. They eventually gain the ability to distinguish the good from the bad, and use that to be able to continue their existence. (and meanwhile, they still continue their limited ability to communicate with the "real" living.)

Ubik also provides strong contrast between an overly commercial world of the future with the "half-life" world. Each have their own challenges, and at times, people are unsure where they belong.

Altogether, it is a good science fiction book that explores many different aspects of life of the 60s when it was written as well as humanity in general.