I think I have mentioned before how I believe that when you write a story -- with every detail you put down, and every question you raise -- you make a promise to the reader. Many of these promises are small and specific, and they are what creates anticipation from page to page.
But the big promise of most books is that you WILL pay off on the issues you raise. If they keep reading, they won't be disappointed. When they close the book on the last page, you promise that they will be satisfied.
But for a soap opera style serial, your promise is a little different. Yes, you make the million little small promises on each detail, and you pay off on them, but you aren't promising a satisfying ending for the whole thing. Instead you promise to never stop. You're like Scheherazade, telling continuous stories which will never fully satisfy, only tease with ever greater promises, so the King will keep listening and not behead you.
So instead of putting your big promise at the beginning of each episode, you put it at the end, with a cliffhanger. The upside of this is that if the writer really does keep paying off on those expectations of the reader, both can be happy forever.
The down side of a serial is that if your reader is expecting satisfaction at the end of a story/episode, they will be very upset if you just hand them a cliffhanger -- i.e. another promise. You become the person who perpetually borrows from others and never pays back.
And for the writer, the down side is that you do have to keep it going. With a TV soap opera, you don't have to worry about burnout so much, because the producers just hire new writers. But for a fiction writer, you can burn out and so can your reader.
There is a difference, though, between a serial and a series.
A good series makes both kinds of promises, and can be the best of both worlds. First, in most series fiction (and series television) each story/episode does have a beginning promise and an ending pay off. Unless you're having a two part special, or a book trilogy, both of which can have cliffhangers at the middle breaks, but will definitely pay of big time at the end.
The Perils of Pauline -- one of the most famous silent serials -- had it both ways, but emphasized the immediate payoff. Unlike later serials of the forties and fifties, the early silents tended to have a whole story in each episode, with an ongoing story arc for the whole series. This is rather like many current TV shows, like Burn Notice or White Collar -- each episode has a plot with a problem to solve in a satisfying way, but there is also a larger mystery and problem going on in the character's lives.
This larger arc may cover a whole season, or even go endlessly from season to season. Both Burn Notice and White Collar, for instance, have mysteries surrounding the main characters. Each season the characters pursue the solution, and usually at the end of a season, they finally find a major answer they are looking for... which leads to another puzzle.
Many mystery books (and an increasing number of sf and fantasy) series have a larger arc for the series characters, though it might not be a whole mystery in it -- it might be more a matter of the detective's struggle with life and family. As often as not we'll pick up the new Archer Mayor or Tony Hillerman or Robert Crais as much to find out what is next for the characters as for the book's main plot.
So with that kind of a series, we're making the "soap opera" promise as well as the regular one. However, because we do tie off each story properly, we cut ourselves a break as a writer. We have met the expectations of the audience. It's like the anticipation and payoffs within the story -- we're writing on a "pay-off as you go" plan, which keeps the audience satisfied.
And in being satisfied, both the audience and the writer can take a break and avoid burnout.
With my serial, I plan to play with three levels of promise, but I have to mess around with it for a bit before I know for sure about the bottom level -- the episodes.
My first plan is to have mini-stories of novelette length, which act as episodes, like an hourly TV show. I want them to stand alone, but be tied together with a definite arc -- which does have to be read in order, like a trilogy. Three or four of them together will make a complete and discrete story. (Which I'll collect into a single-book omnibus.)
That's two levels of promise -- both of the regular "you will be satisfied when this part is done" type. I am not sure about the episodes, though. How much should they stand alone, and how much should be they a part of the larger whole? They will have a teaser into the next story, and if they have to be read in order anyway...should it be a full cliffhanger?
The other level of promise is that the story will have a much larger arc of the characters and place -- more of the unending type, like a soap opera or like those TV shows, although instead of tying the thing together with a critical issue to the main characters, I plan to push into new territory by bringing forward the minor characters and puzzles, and letting them develop and take the stage.
In that way I hope to meld all of the best aspects of the serial into it. It's not a new idea, and there are authors currently doing something like it (Lee and Miller come to mind) but at the same time, most current authors are doing this on the macro level, with large, long books. I want to get back to the shorter individual stories of a hundred years ago, when this was the usual way of telling a story.
In the meantime, the night clerk called in sick at The Day Job and I put in a longer day's work than I expected, and I might end up doing the same tomorrow. In either case, I'll be footling along with out plan, but perhaps getting somewhere interesting with the story.