Entry to Elsewhen is a collection of science fiction

Science fiction

Science fiction is a genre of fiction dealing with imaginary but more or less plausible content such as future settings, futuristic science and technology, space travel, aliens, and paranormal abilities...

 short stories by John Brunner

John Brunner (novelist)

John Kilian Houston Brunner was a prolific British author of science fiction novels and stories. His 1968 novel Stand on Zanzibar, about an overpopulated world, won the 1968 Hugo Award for best science fiction novel. It also won the BSFA award the same year...

, published in 1972. It contains the following stories:

• Host Age first appeared in New Worlds SF in 1955.
• Lungfish first appeared in Britain in Science Fantasy
  Science Fantasy (magazine)
  Science Fantasy, which also appeared under the titles Impulse and SF Impulse, was a British fantasy and science fiction magazine, launched in 1950 by Nova Publications as a companion to Nova's New Worlds. Walter Gillings was editor for the first two issues, and was then replaced by John Carnell,...
  
   in 1957.
• No Other Gods But Me first appeared in what the acknowledgments page of this book describes as a "shorter and substantially different form" as A Time To Rend in Science Fantasy
  Science Fantasy (magazine)
  Science Fantasy, which also appeared under the titles Impulse and SF Impulse, was a British fantasy and science fiction magazine, launched in 1950 by Nova Publications as a companion to Nova's New Worlds. Walter Gillings was editor for the first two issues, and was then replaced by John Carnell,...
  
   in 1958. The version included in Entry to Elsewhen was written in 1966 and first appears in this collection.

The above attributions notwithstanding, the book's acknowledgments page notes that "All three stories have been completely revised by the author for the present book."

Host Age

The first story takes place in what appears to be the relatively near future. Set in London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

, it deals with the appearance and spread of a mysterious new plague

Pandemic

A pandemic is an epidemic of infectious disease that is spreading through human populations across a large region; for instance multiple continents, or even worldwide. A widespread endemic disease that is stable in terms of how many people are getting sick from it is not a pandemic...

. The plague defies all efforts to treat it or stop its spread, showing varied symptoms in different victims and mutating rapidly. A sinister aspect soon appears when scientists making progress in fighting the plague are repeatedly sabotaged by unknown persons. Also, the plague seems to be spread by multiple typhoid Mary individuals, found unconscious on trains with large amounts of cash but no identifying information.

Eventually it is discovered that the plague is being spread by human military forces who have traveled through time from several centuries in the future. The head of this group explains that the plague was developed by an aggressive alien species with the purpose of destroying humanity. The plague's effectiveness derives in part from atrophied immune systems resulting from long-term prevention of exposure to any infectious agent. Traveling to the past is a desperate measure to introduce the virus to humans with more robust immune systems in the hope that the survivors will be better able to resist the virus when the alien species creates it.

Lungfish

This story takes place aboard a multi-generational spaceship traveling from Earth to a planet orbiting Tau Ceti

Tau Ceti

Tau Ceti is a star in the constellation Cetus that is spectrally similar to the Sun, although it has only about 78% of the Sun's mass. At a distance of just under 12 light-years from the Solar System, it is a relatively close star. Tau Ceti is metal-deficient and so is thought to be less likely to...

 with the goal of establishing a colony. The story's action concerns the end of the journey. The trip has taken 37 years, and by now the crew is composed of two groups—the Earthborn, the surviving members of the original crew, and the Tripborn, descendants of the original crew, who have lived their entire lives aboard the ship.

On reaching the destination planet, the Tripborn refuse to leave the ship. Never having lived on a planet, they don't seem to see the appeal. Additionally the idea causes severe agoraphobia

Agoraphobia

Agoraphobia is an anxiety disorder defined as a morbid fear of having a panic attack or panic-like symptoms in a situation from which it is perceived to be difficult to escape. These situations can include, but are not limited to, wide-open spaces, crowds, or uncontrolled social conditions...

, as experienced by one Tripborn crew member who makes a landing on the planet and must be retrieved by remote control. The Earthborn crew members employ a variety of means to make the Tripborn less comfortable on the ship, such as Psychoactive Drug included in the food supply and subtle background sounds designed to cause unease. However this fails to move the Tripborn, even despite the fact that the ship will be unable to support the full crew's life for more than a few weeks more. The Tripborn also note that it's difficult to accept the Earthborn crew's rosy predictions for the future when the overall mission calls for the Earthborn to return home, leaving the Tripborn to establish the colony.

Since the ship's cargo includes the necessary tools to build a city suitable for 10,000 inhabitants on the destination planet, the Earthborn crew suggests that they instead be employed in the construction of a second spaceship. The reduced crew on the original ship could be supported by the ship's systems, and the Earthborn crew would no longer need the original ship for the return voyage.

The story ends before this plan has been carried out, leaving the reader to imagine whether the plan would be successful.

No Other Gods But Me

As with the first story, this story takes place on the near-future Earth. Colin Hooper is a man who is completing recovery from a severe mental breakdown, which significantly included hallucination. After repeated chance meetings with Vanessa Sheriff he becomes unnerved by the fact that whenever she is present, the hallucinations return. However, she sees them as well. Their meetings are repeatedly interrupted by the appearance of a man calling himself Kolok, who makes dire predictions if they should keep meeting, but offers no details of what might occur.

Vanessa marries a man who is involved with an organization calling itself Real Truth, which she describes as a cult

Cult

The word cult in current popular usage usually refers to a group whose beliefs or practices are considered abnormal or bizarre. The word originally denoted a system of ritual practices...

. The "Real Truthers" beliefs include a belief in the supremacy of human thought as the primary force in the universe, and the idea that by working together they can think into existence someone who they describe as the Perfect Man.

After being drawn into a meeting of Real Truth, Colin and Vanessa accidentally cross over into a parallel-universe Earth in which mental powers such as psychokinesis

Psychokinesis

The term psychokinesis , also referred to as telekinesis with respect to strictly describing movement of matter, sometimes abbreviated PK and TK respectively, is a term...

 are practiced by a number of adepts, who use these powers to enslave the rest of the population. It is explained that these abilities originated thousands of years past as the result of a mutation which the adepts carry. The leader, Telthis, is the one with the strongest mental powers, and has been using his abilities to influence events on Colin and Vanessa's Earth with the purpose of eventually invading it and ruling both Earths. It was Telthis's efforts which caused Colin's breakdown and hallucinations. Telthis also manipulated Colin and Vanessa into their apparently random meetings, because they also carry the genetic mutation of the adepts on Telthis' Earth, and he hopes that by bringing them together they will eventually have children and promote psychokinetic and other mental powers. Kolok, it turns out, is Telthis' chief opponent, who has appeared to Colin and Vanessa in the hope of preventing this.

Colin and Vanessa manage with Kolok's help to escape from captivity and return to their own Earth. Shortly afterward, Telthis' invasion begins. However he discovers that his mental powers do not function outside of his own Earth. He and his soldiers are attacked by an angry mob and carried off by police.