People asked me a little about series bibles. I can't speak to anyone else, but I'll tell you what mine are usually like. (CONT'D)

My series bibles tend to be about 18-24 pages long, before illustrations (which I like to use when possible.) I usually structure them thusly:(CONT'D)

1: Overview of the show.
2: A little section on the tone of the show and comparisons to other works that help the reader visualize it.
3: An extended description of the protagonist and his/her story. (TV is about character first, then plot!)
4: A section on the other characters.

5: If it's a genre piece, a section on the bigger world/universe of the show.
6: A breakdown of the pilot, usually pretty detailed.
7: A breakdown of the big arc of the first season, maybe breaking out all the episodes, maybe only a few.
8: A shorter breakdown on seasons 2-?

9: A conclusion, hopefully that restates the themes of the show in a compelling way.
That's what I find typically works for me, anyway. But you do what works for you!

Note: if you're lucky enough to have your show picked up to series, expect that you will diverge MASSIVELY from the Bible, especially past season one. But you will be surprised at how many nuggets from your original thinking end up getting used in some form.

I recently developed an animated show that got picked up for 52 episodes. I gave them a MASSIVELY detailed bible (we even convened a room of 10 writers for 2 days to help brainstorm) & now that the staff is rocking & rolling, they're doing their own thing...

...but still using LOTS of elements from it. It was far from wasted time.

In conclusion, the studio will probably make you write a bible for your show for not much money, it's a massive pain in the ass to write, but it forces you to do a lot of world building and thinking early on about your own show beyond the pilot, so on the whole it's a good thing.

Any other TV writers who have written show bibles, feel free to chime in on how you structure yours, length, etc.

Just as a sample, here's the table of contents for bible Ash & I did for the Terminator show that was supposed to run alongside Terminator Genisys & the sequels that never happened. It's exceptionally long because there was a LOT of world building & explanation required.

The section on tone is HUGELY important to the audience. Here's how I described the tone of my supernatural thriller for Skydance and Freeform, Iron Age (and how I described magic working!) No need to be fancy, just paint a picture for your readers!

And yes, I am still proud of "J.R.R. Tolkien meets J.J. Abrams" as a tonal description. :)

Conclusions are important! Here's how I wrapped up the Iron Age bible. Think about the emotional charge you want to leave the reader with. And yes, I'm a pretentious motherfucker and love to use literary quotes, song lyrics, etc. to help set the mood for the reader.