Just seen Random Quest, the BBC4 drama based on the John Wyndham story. It was interesting, but took a very different tack on the alternative universe from the original Wyndham story where World War 2 never happened. In that respect Quest for Love (an earlier film version of the same plot, and starring Joan Collins!) was a closer rendering, except for the cheesy melodramatic ending; Random Quest was closer to Wyndham's story there. I'm surprised BBC Radio 4 hasn't dramatised it; I'm sure it would make a good story on Radio.
In Random Quest, an explosion sends our hero into an alternative timeline where he is married, and a successful writer, not a physicist. What happens there, and when he returns, makes an intriguing story.
For a good review of the story, see the British Invaders Podcasts at:
Random Quest was a 2006 BBC Four adaptation of a 1960s story by John Wyndham. Why is Colin Trafford waking up in a place that he doesn’t recognize? Why do his friends appear to be so very different? Who is the mysterious Ottilie Harshom?
Random Quest was a one-hour BBC drama based on a story by John Wyndham. Colin Trafford has found himself in an alternate version of reality. Can he find someone he knew in a different world?
Parallel World Stories on TV can be seen in 2 categories. One would be when someone goes across from one world to another, the second is just when the world is portrayed as different because of a change in history.
With films, the two genres can be easily seen: the Random Quest film version Quest for Love does that, and something like Fatherland is an example of the second type. Both are about parallel worlds, but one has a transfer, one doesn't.
Wyndham incidentally also had another story about parallel worlds in The Seeds of Time collection called Opposite Number, but it isn't nearly as strong as Random Quest.
Book wise, Wyndham visited it twice in his short stories (Random Quest / Opposite Number). John Brunner had a universe where the Armada won (Times without Number), and Ward Moore had one where Lincoln lost (Bring the Jubilee) - both have time travel, and our universe crops up towards the end. Poul Anderson had "Time Patrol" in which there are changes made, and the heroes have to set the world back after they return to a different present. Asimov had "reality changes" in "The end of Eternity", with alternate earth timelines.
The other kind of alternate world occurs in Kinglsey Amis "The Alteration" (no reformation in England), Philip K Dick's "Man in the High Castle" (Hitler and Japan won), and Robert Harris "Fatherland" (Hitler won). Those are stories set in alternative timelines, but there's no way between that timeline and this.
On TV, the Gerry Anderson show Journey to the Far Side of the Sun (also called Doppelganger) is an interesting variant, as both the Earth and its duplicate exist in the same dimension.
It occurs in Dr Who in Inferno, and Rise of the Cybermen (and linked stories to that). Star Trek notably had "Mirror Mirror".
Red Dwarf revisited it a number of times. In "Parallel Universe" the crew meet alternative versions of themselves: the analogues of Lister, Rimmer and Holly are female, while the Cat's alternate is a dog. "Dimension Jump" introduces a heroic alternate Rimmer, a version of whom reappears in "Stoke Me a Clipper". The next episode, "Ouroboros", makes contact with a timeline in which Kochanski, rather than Lister, was the sole survivor of the original disaster; this alternate Kochanski then joins the crew for the remaining episodes.
Probably the largest number of Parallel Universes is in Star Trek Next Generation, where there is this wonderful line when the universes all converge:
Lt. Commander Data: The rate of quantum incursions is increasing exponentially. At this rate, the sector will be completely filled with Enterprises within three days.
La Saint Hélyi - Aniet ch'est la Saint Hélyi. *Today is Saint Helier Day.* - Saint Hélyi
5 hours ago