Foundation by Isaac Asimov is one of the earliest science fiction ongoing story lines. Previous authors would have the same set of characters in the same universe with self-contained stories. Foundation kept the universe the same and changed the characters while furthering the same extended storyline. Asimov has thought out a 1000 year storyline and set these stories against that backdrop. The result is a classic in science fiction.
Hari Seldon is the founder and sole practitioner of psychohistory. Psychohistory is the study of how groups of people would act going into the future. It is unable to predict what an individual would do, but is fairly accurate at predicting large groups. And the flip side of this study is how to make changes to the future by altering the present. Seldon is called before the government to explain his doomsday predictions. He talks about the decline and fall of the Empire (since Gibbon’s Decline and Fall of the Roman Empire was one of the sources for these stories) and how he can use psychohistory to change the coming dark age from 40,000 years to less than 1000. He pushed for an encyclopedia to be created which will document all human knowledge and be run from a distant enough location that Empire politics won’t affect it. Seldon gets his wish and thousands of people are moved to the planet Terminus…except for Seldon who has to stay.
The stories then follow the people on Terminus with decision points that are punctuated by holographic recordings of Hari Seldon clarifying what has happened and what their new challenges will be. The stories discuss all topics of science fiction from weapons to starships to new religions. And Asimov makes them all work within his background by the sheer brilliance of his writing. Asimov writes stories where a lot of action happens off camera and characters have discussions afterwards explaining what is or has happened. So, even though most of the stories feature mainly talking heads, Asimov’s writing makes it work.
Asimov returned to the Foundation Universe 30 years later and wrote a few more novels to further the story. Those will be reviewed separately and probably should be avoided. The original Foundation stories are one of the pillars of science fiction by one of the grand masters. Highly recommended.