The Anatomy of Story is another book about writing for cinema, and it more or less begins by arguing against everything taught by Save the Cat. The three act structure is wrong. Thinking in terms of inciting incident and rising action will get you nowhere because these ideas are generic. Relying on genre is the way to produce a predictable and formulaic result. The truth comes from within.
Truby encourages the writer to start by identifying topics that matter to them. “Write a story that will change your life,” he says, and then suggests some ways you might identify what topics and themes are particularly important to you. In this respect, it feels like a less dogmatic and more personal approach to some of Egri’s advice.
Once the writer has identified what sort of story she finds most compelling, Truby suggests looking (among other things) for the main character’s “basic action,” the thing that character does most consistently or most importantly in the story — Michael Corleone’s act of revenge, Luke Skywalker’s hand-to-hand combat against evil — as well as a design principle that will help structure the story, and important end-of-story choices that will be finely balanced between two almost-equally-desirable (or undesirable) outcomes.
All of this thinking could equally well be the preparation to find a good mechanic for your narrative design. Elizabeth Smyth’s Bogeyman is a horror story about abuse in which every choice the player makes is about obeying or defying the abuser. Papers, Please is about whether to comply or quietly disobey orders, in a host of ambiguous circumstances.
Truby also spends quite a bit of time on moral jeopardy as the driver of a good story: “will the hero do the right thing, and will he do it on time?” How do we build up the stakes for this question, how do we show the hero in danger of doing the wrong thing, and how do we contrast the hero’s values with those of an opponent?
In short, like a number of others offering plotting advice, Truby produces quite a few diagrams of possible structures, and spends a lot of pages demonstrating how various classic movies match up with his dicta. But I found these instructions more compelling than many of the others, because Truby is concerned with content on a deeper level than McKee, and certainly on a deeper level than Blake Snyder.
Truby’s advice about how to avoid having your main character expose all their moral views through dialogue is also important, and gets at a failing I see in a fair amount of interactive fiction (including plenty of my own early work). Putting characters in a context to discuss their moral views is prosier and less compelling than allowing them to act on those views and observe the consequences.
If you were going to read just one of the standard screenwriting advice books, with an eye to what it can offer interactive narrative, I’d probably make it this one.
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A side note on structure: Truby talks about branching story, but he doesn’t mean interactive fiction. He’s using this to describe a structure in linear narrative that presents elements of many different substories next to each other.
Emily Short's Interactive Storytelling 
That “branching” is what I call “fractal writing”.
Wonderful! I just recently started reading/enjoying this, and then I get your approval ; ). Truby’s first chapters are definitely what reeled me in (as you say his focus on intent rather than know-how and formula).
A question, if I may: I’m not much of a story-writer (as in coming up with the ‘adventure’ part of the equation), but I’m working on a densely interactive VR diorama (http://naam.itch.io/apotu) and a story/plot is starting to emerge from all the incidental detail popping up everywhere, taking shape in my head. It’s more of a situation/slice-of-life thing than a story per se. What would you (or any other reader!) say is a good way to come up with narrative cues to divulge this to the visitor?
I guess I’m mainly struggling with process – how to come up with just the right bits of information to relate to the listener, and how to make that matter. Truby’s book certainly made some elements click into place here!
Sorry for the wordiness, and thanks!
naam
Start by identifying the bare minimum. What are the 3-7 most important events or beats the player must know about in order to understand your story? What traces might those events have left on the world?
Recordings of from eyewitnesses (meaning artifacts such as diary entries, ship logs, etc) are less powerful than actual evidence of the event itself having marked the environment, but sometimes one must fall back on a bit of exposition from the past in order to make clear what has happened.
Whatever you pick, make these traces notable and place them where the player cannot avoid encountering them in the process of traversing your world. And by “notable”, I mean ideally things the player must actually interact with in order to proceed through the space; or, failing that, environmental set pieces large enough that it’s very difficult to miss them by looking the wrong way.
Now, what are the attitudes of the characters who participated in the story? What were their motives? Why did they do what they did? These can be even harder to communicate without expository elements in the characters’ own voices, but it’s possible to work with clues — foreclosure bills, discarded wedding ring, prescription medication for a chronic illness.
As a general rule, place the clues for these motives where they will be found after the player has found the event they motivated, so they have had a chance to wonder why something happened before discovering a reason.
If you must include diary entries or logs or similar things, make those elements do as much work as possible: have them speak in a character’s voice, have them communicate personality and side detail; have the character who is writing the diary entry be perhaps focused on something quite different from what the player is trying to find out by reading it, and reveal the truth only as an incidental.
Some refs:
* Clara Fernandez-Vara on Indexical Storytelling, https://www.gdcvault.com/play/1016815/Environmental-Storytelling-Indices-and-the
* Plot-shaped Level Design, https://emshort.blog/2016/05/18/plot-shaped-level-design/
* Harvey Smith, Matthias Worch on Environmental Storytelling, https://www.gdcvault.com/play/1012647/What-Happened-Here-Environmental
Thank you! That makes so much sense, wonderfully succinct read!
Yes, trying to do as much with the environment as I can, and coupling it to interaction. I do have a journal mechanism (the visitor can use a typing machine to type out the thoughts of the protagonist, hoping this places them in their boots). Already discovered how hard it is NOT to use that to ‘explain’ the weirder magical-realist elements : ).
Thanks again, also for the references! That’s my weekend sorted, probably.
Cheers,
Naam