Ubik by Philip K. Dick
Nobody but Philip K. Dick could so successfully combine SF comedy with the unease of reality gone wrong, shifting underfoot like quicksand. Besides grisly ideas like funeral parlors where you swap gossip for the advice of the frozen dead, Ubik (1969) offers such deadpan farce as a moneyless character's attack on the robot apartment door that demands a five-cent toll:
"I'll sue you," the door said as the first screw fell out.
Joe Chip said, "I've never been sued by a door. But I guess I can live through it."
Chip works for Glen Runciter's anti-psi security agency, which hires out its talents to block telepathic snooping and paranormal dirty tricks. When its special team tackles a big job on the Moon, something goes terribly wrong. Runciter is killed, it seems--but messages from him now appear on toilet walls, traffic tickets, or product labels. Meanwhile, fragments of reality are timeslipping into past versions: Joe Chip's beloved stereo system reverts to a hand-cranked 78 player with bamboo needles. Why does Runciter's face appear on U.S. coins? Why the repeated ads for a hard-to-find universal panacea called Ubik ("safe when taken as directed")?
The true, chilling state of affairs slowly becomes clear, though the villain isn't who Joe Chip thinks. And this is Dick country, where final truths are never quite final and--with the help of Ubik--the reality/illusion balance can still be tilted the other way. --David Langford, Amazon.co.uk
The novel takes place in the "North American Confederation" of 1992, wherein technology has advanced to the extent of permitting civilians to reach the Moon and psi phenomena are common. The protagonist is Joe Chip, a debt-ridden technician for Glen Runciter's "prudence organization", which employs people with the ability to block certain psychic powers (as in the case of an anti-telepath, who can prevent a telepath from reading a client's mind) to enforce privacy by request. Runciter runs the company with the assistance of his deceased wife Ella, who is kept in a state of "half-life", a form of cryonic suspension that gives the deceased person limited consciousness and communication ability.
When business magnate Stanton Mick hires Runciter’s company to secure his lunar facilities from telepaths, Runciter assembles eleven agents for this task. The group includes Pat Conley, a mysterious young woman who has an unprecedented parapsychological ability to undo events by changing the past. Joe Chip is shown at several points to have sexual feelings for the defiant Pat Conley, who once gives the impression of reciprocating them.
When Runciter, Chip, and the others reach Mick’s moon base, they discover that the assignment is a trap, presumably set by the company’s main adversary Ray Hollis, who leads an organization of psychics. A bomb explosion apparently kills Runciter without significantly harming the others. They rush back to Earth to place him in half-life.
Afterwards, the group begins to experience strange shifts in reality. Consumables, such as milk and cigarettes, begin to deteriorate prematurely. Also, the group sees Runciter's face on coins and receives strange messages from him in writing and on television. Most of these messages imply that Runciter is in fact alive, while the others are in half-life, or "cold-pac" as it is informally called. Group members who separate from the group are found dead, in a gruesome state of decomposition.
The reality gradually shifts backward in time until the group finds itself in a world resembling the United States in 1939. They try throughout to deduce what is causing these strange occurrences, prevent each other from dying, and find a mysterious product called Ubik, which is advertised in every time period they enter. Messages from Runciter indicate that Ubik may be their only hope of survival.
Ultimately, Joe Chip learns that Runciter, in fact, was the sole survivor of the explosion on the moon, and that his messages to the group are the result of his attempts to communicate with them while they are in half-life. The regressing world in which they find themselves is discovered to be the product of Jory Miller, another half-lifer whom Runciter encounters earlier in the story while communicating with Ella. It is revealed that Jory devours the life force of other people who are in suspended animation to prolong his own present existence. Of the group of anti-psychics and technicians, only Joe Chip eludes him, aided by the substance called Ubik. This substance, whose name is derived from the word "ubiquity", has the property of preserving people who are in half-life. Joe Chip is instructed in its use by Ella Runciter, who is en route to a reincarnation.
In the living world, Glen Runciter encounters several coins showing Joe Chip's face. He suspects that this is "just the beginning."
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