Story CircleInteractive fiction
The main kinds of interactive fiction, a short history of the form, and the shapes a branching story can take.
Writing guide
How to write a branching story
To write a branching story, build a short single-path trunk first, then fork only where the character stands to lose something. Limit how many paths a fork opens and how long a branch may run, write choices as intentions, keep each branch’s facts separate, merge with a trace or run to an ending, and close every path cleanly.
This guide is for the person about to write one. Every step moves the same example forward: Mina, a courier carrying a sealed envelope through a city-wide blackout. If you want the form itself — where it came from and the kinds it takes — the guide to interactive fiction covers that; this one stays on the writing side.
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Definition
What is a branching narrative?
A branching narrative is a story where the reader chooses at certain points and the choice genuinely changes what follows.
- Trunk
- The part of the story every reader goes through before the first fork.
- Fork
- A chapter with more than one continuation below it: the point where the reader chooses.
- Branch
- One continuation after a fork, with a middle and an ending of its own. In a numbered tree, the two continuations of chapter 1 are 2.1 and 2.2: the first number is the depth, the second the branch.
- Path
- The chain of chapters one reader actually reads, from the first chapter to an ending.
- Ending
- The chapter where a path finishes. A branching story with several of them is a story with multiple endings.
Step by step
How do you write a branching story step by step?
Trunk, fork, limits, choices, branch cards, merges and endings: each step is a decision that keeps the tree from growing faster than it can be written.
Write a short single-path trunk first
Before the first fork, readers need to know who wants what and what is at stake. A few chapters on one path give the branches ground to grow from; stories that fork on page one rarely give any path enough room to deepen.
Example: The first three chapters stay on one path: a city-wide blackout, a sealed envelope addressed to the mayor, and Mina, a bicycle courier, realizing the sender is her missing brother.
Fork where the character stands to lose something
Test a candidate fork with three questions: will the two paths still produce different scenes three chapters later, can the reader see what they are giving up, and is there someone to write this branch? If any answer is no, you have one road, not two.
Example: “Left street or right street?” is not a fork. “Deliver the envelope unopened, or read what her brother wrote?” is: each option costs Mina something.
Set your limits before you write
Fix two numbers up front: how many paths a fork opens and how many chapters a branch may run. Limits agreed in advance cause no arguments later, and they stop the tree from growing faster than anyone can write it.
Example: Two paths per fork, a fork every four chapters. A branch runs three chapters at most; on the fourth it either rejoins the trunk or reaches its own ending.
Write each choice as an intention, not a direction
Readers should choose what they are willing to risk, not which way to walk; what happens next is still yours to write. An option that states intent gives the choice meaning and tells whoever writes the branch what the character is after.
Example: Not “Open the envelope” but “Risk breaking her brother’s trust”; not “Ride to city hall” but “Put the city ahead of her brother”.
Keep a branch card for every branch
Trunk facts are true on every path; branch facts are true on one. Put three lines at the head of each branch: who is alive, who knows what, what has changed since the trunk. Sibling branches do not know about each other, so nothing is borrowed from the one next door.
Example: Branch card for the “read it” path: “Mina knows where her brother is hiding. Her front wheel is buckled. The mayor knows nothing.”
Merge with a trace, or run the branch to its own ending
A merge chapter has to be true for readers arriving from different paths: open neutrally, keep the difference in what the character knows rather than in events, and leave a trace of the road they took. If something irreversible happened on a branch, it cannot merge; it runs to its own ending.
Example: Both paths meet at dawn: “The lights came back one street at a time.” In the second paragraph, readers from the “read it” path see the buckled wheel; readers who delivered the envelope see the mayor’s receipt in her pocket.
Make an ending inventory and close every path cleanly
For each ending write three things: its name, the question it answers and the price the reader paid to get there. If two endings answer the same question, one of them is redundant. The last sentence of a final chapter should close a door, so readers learn the path has ended from the prose, not the interface.
Example: “The one who kept the seal”, “the one who read it” and “the one who paid”: three endings, three separate questions. The full inventory is in the table below.
Inside a branch, scenes are built the way they are in any story: want, obstacle, change. For those basics, see how to write a story for beginners. They matter more here, because in a branching book any chapter can be someone’s starting point.
Planning
How do you plan a branching story?
Decide whether you write the spine or the branches first; the middle route that works in practice is to write the spine but leave its ending open.
| Approach | How it works | What you gain | What you pay |
|---|---|---|---|
| Spine first | Write one path end to end, then open branches off it. | You know the ending; every branch knows where it rejoins, and merge chapters get easier. | Branches added later read like detours, because the spine is complete without them. |
| Fork first | Branch early and write each path as its own story. | Branches carry equal weight; none feels like an appendix. | The hardest version to finish: every path must earn an ending. |
| Middle route | Write the spine but not its ending; know three chapters ahead. | You know where branches attach, and they stay part of the story. | You decide the ending again when you get there. |
A chapter number is a coordinate, not a memory: “2.2” tells readers where they are, not what happened there.
Give every branch a name that says what it is — “the read-it path”, “the delivery” — so readers remember the road they did not take.
When several people write the book, nobody writes the whole spine in advance; a main path is declared instead, and branches leave from it. Short definitions of trunk, branch, path and ending are also in the glossary of creative writing terms.
Endings
How many endings should a branching story have?
The test matters more than the number: each ending should answer a different question and cost something different; in practice three to five endings are enough for most books.
| Ending | Question it answers | Price the reader pays |
|---|---|---|
| The one who kept the seal | Can Mina be trusted? | Her brother stays in hiding. |
| The one who read it | Where is her brother? | She loses the mayor’s protection. |
| The one who paid | Who caused the blackout? | Her brother’s name is made public. |
Endings should differ by what they cost, not by whether they are happy.
A reader who finds the good ending stops. A reader who finds endings with different prices comes back.
Why three to five: readers explore on the second and third pass and start skimming by the fifth. If two endings say “yes” and “no” to the same question, you have one ending in two moods. A short branch that closes properly is worth more than a long one that simply stops.
Mistakes
What mistakes break a branching story?
The most expensive mistake is opening a branch for a choice that costs nothing; merges without a trace and details borrowed from a sibling branch come next.
Five kinds of false choice
The cosmetic choice
Same outcome, different sentences. A reader who tries both feels cheated, and the branch was written for no one.
The two-doors choice
Left door or right door. A choice unrelated to what the character wants only asks the reader to roll dice. Ask about a priority, not a direction.
The flagged choice
One option is obviously wrong because the prose has already said so. An option carrying a visible penalty is not an option.
The information choice
“Choose which thing to find out.” A fine idea that does not need a branch: one chapter can carry either piece of information.
The deferred choice
The consequence is always pushed to the next chapter. When the branch ends, the reader never sees a return on the decision.
- A choice at the end of every chapter. Two or three well-built forks carry thirty chapters; a choice in every chapter makes the book impossible to finish, not richer.
- A branch with no declared exit. When you open it, say whether it rejoins at chapter N or runs to its own ending. Otherwise it dangles the moment its writer stops.
- A merge with no trace. If nothing is different after the paths meet, the reader’s choice has been deleted after the fact.
- Writing upward. A branch may reinterpret the chapters above it but not change them; if it has to, it is a different book.
- Counting on a second read. Most readers take one path and never come back, so every branch has to feel complete on its own.
Together
How do several writers branch one story?
Branching suits collaborative writing, because two writers can work on sibling branches at the same time, but it brings three new problems: different voices, silent contradictions and who writes the ending.
Different voices
Sibling branches come from different writers and readers meet them back to back. A difference in tone is richness; a difference in narrator, tense or chapter length is a defect. The fix is to write those down as rules when the book starts.
Silent contradictions
Two branches assume different versions of the same trunk fact, and nobody notices because nobody reads both. The fix is one place for trunk facts, next to the character notes, read before writing a branch.
Who writes the ending
Whoever opens a branch does not have to finish it, which is the best property of the form. But closing is harder than opening. The fix is visibility: make it obvious which branches are close to an ending.
Branching stories with one author die of too many branches; ones with many authors die of inconsistency.
The first needs a limit, the second a written rule. The rest of the method is in the guide to collaborative writing.
In practice
How does branching work in Story Circle?
In Story Circle a branching story starts when whoever sets up the book answers “How should the story move?” with “Branching”; the limits from step three become settings on the book itself.
For whoever sets up the book
- Branching. Two different continuations can be written under a chapter, and readers choose which one to read.
- Branch interval. Fork at every chapter, or at intervals such as “Every 4 chapters”, where the story runs on one path for four chapters and then splits in two.
- How many different endings at most. An optional cap; once it is reached, no new forks open and the open paths continue on a single line to the target.
- How many chapters the book should have. Every path that reaches that number is an ending.
These structure settings cannot be changed once the book is live, which is why the limits are worth thinking through before setup.
For the writer
- An open branch is written by the first writer to start it. The two branches of one fork can be written by two writers at the same time.
- Your writing time is whatever the book’s owner chose, between 1 and 72 hours (24 by default). If it runs out, the branch opens to everyone again and your draft stays with you.
- To start writing a branch you need to have read the chapters above it on that path, but not its sibling branches: the app’s version of “siblings do not know each other”.
- If the book’s owner turned on the consecutive-author rule, you can write directly under your own chapter only after a waiting period (currently 6 hours), so others get a chance to go first.
- Every chapter passes an automatic content review before it is published.
- Every chapter has exactly one parent, so branches do not merge in the app: at step six a branch runs to its own ending, and the branch interval and the cap on endings keep the tree in check instead.
For the reader
- At a fork, readers see “The book splits in two here” and pick a path with “Continue this path”. The choice is saved, and they can come back to the other path later from the Paths screen. Once there is reading data, each option also shows what share of readers chose it.
- The path map shows the main path, the alternative paths, the endings found so far and the branches waiting to be written.
- At the end of a path nobody has continued yet, the reader sees “Start writing”: going from reader to writer is one tap.
The full writing cycle is on how Story Circle works.
Questions
Frequently asked questions
Is a branching story the same as a story with multiple endings?
Usually, but not always. A branching story’s paths can merge again and arrive at a single ending, while a story with multiple endings has at least two paths that finish differently. In Story Circle branches never merge and every path that reaches the book’s target length is an ending, so each branch of a branching book runs to an ending of its own.
Does every chapter need to end in a choice?
No, and assuming it does is one of the most expensive mistakes in the form. A fork is not the same thing as a chapter ending. Two or three well-placed forks will carry a whole book, while a choice at the end of every chapter produces a tree nobody can finish. Put a fork where the character has something real to lose, not at a fixed interval.
Can branches merge back together?
On paper, yes; merging is the strongest tool for keeping a branching story finishable. The condition is that the merge leaves a trace, so readers still feel which way they came. In Story Circle every chapter has exactly one parent, so branches do not merge; the branch interval and the maximum number of endings keep the tree in check instead.
Can one branch refer to what happened in another?
No. Sibling branches do not know about each other: what happened in 2.1 did not happen in 2.2. A branch may build only on the chapters above it and on facts that hold everywhere in the book. Borrowing a detail from a sibling branch is the most common continuity error in multi-author branching stories.
What happens if I cannot finish a branch?
An abandoned branch is a road that leads nowhere, and it hurts a book more than a missing branch would. There are two honest exits: close it with a short but definite ending, or leave it somewhere another writer can pick it up. In Story Circle, if your writing time runs out the chapter opens to everyone again and another writer can continue it; your draft stays with you.
Can you write a branching story without planning it?
You can, as long as two numbers are fixed up front: how many chapters a branch may run before it ends or rejoins, and how many paths a fork may open. With those limits in place, the rest can be discovered while writing. Without them, not planning does not make the book bigger; it makes it fall apart.
What tools can I use to plan a branching story?
Paper goes a long way: a tree drawn on one sheet, a branch card for each branch and an ending inventory. Twine, a free open-source tool, is built for writing and linking branching passages on your own. Story Circle is a different kind of tool: it lets several writers write the branches of one book, with each open branch written by whoever starts it first.