Has anyone ever written two book series at the same time that have different plots but merge into a single series later on? like one series focuses on 1 plot and its set of characters; the other on a different plot and a different set of characters; and the two plots intertwine later on.
No, but one I started writing a stand-alone novel, then added its characters into the second-to-last book of another series I was writing. In the end, the series fell through, and I'm sticking with the novel. I still think it would work, however, provided that the reader does not have to read both series to be able to understand them when they merge.
I've done that. It was a three novel series, where the characters spit at the end of book one, and throughout book seven pursued seperate stories, which had subtle influences on each other, and were reunited at the end of book two.
except i dont mean a series splitting then reuniting. heres and example water and earth series are published at the same time with different plots and characters (same setting and possibly some characters in both) the series later on merge into mud (water+earth=mud); the characters meet and plots intertwine. the interesting part is that the protagonists are each others antagonists allowing the readers to root for one side or the next. (mud water and earth are just filler names)
I parrot myself that it's okay, provided you don't expect the reader to have to read both water and earth series (since that's at least 4 books, probably more) to appriciate the 'mud' one.
Oh, I see. Stephen King does a similar thing with his Dark Tower series- amalgamates characters and plot devices from many of his novels into the series.
yeah it sort of is like that. also you the whole point of having two series is to allow the readers to see both protagonists as protagonists and then decide which protagonist they like more or has a more just cause (In example in deathnote Light and L are protagonists but are each others enemies... many people like L better than Light and vice versa. They either think that Lights good intentions are ill put or that L shouldn't stop him. except that in deathnote Light is a more major character because the series focuses the most on him; this would allow for both protagonists to be equally major because they have their own stories)
I think it's an excellent idea. Though as a word of caution, like Mumblingsage said, make sure if a reader was only following the "water" series and never read the "earth" series they could enjoy and understand the "mud" series just as much as someone who had read both. Also, you'd have to make sure the "mud" series was on very neutral ground protagonist/antagonist-wise or else those who were fans of the "water" series (or never read the "earth" series) would feel cheated if their beloved protagonists became obvious (or even subtle) villains.
I think it's a great idea. One way to think about writing it might be to write "Mud" first, and then write earth and water as "prequels". When you release them just release earth and water first, then release mud. Just because mud was written first doesn't mean it has to be the first book read. This might make the writing easier for you in terms of keeping the characters straight etc.
that might just work. also i will be trickey to make mud easy to read if someone hasn't read both books. but i may be accomplishable