Hidden Door 发布叙事骨架框架以规范 AI 游戏剧情结构

Flexibility is one of the great strengths of story games that use LLMs — players can choose to play in any world, with any character, limited only by their imagination. However, without any structure, stories feel flat, random, and unsatisfying. This is a common failure case in LLM storytelling.

Stories have structure: rising and falling action, setup and payoff, character development. Choices and their consequences. The most satisfying moments in the story all come from that structure — the gun from act one being fired in act three, the kiss after seasons of will-they-won’t-they, the former villain teaming up with the protagonists after a well-earned redemption arc. Structure isn’t restrictive, simply constraining what the player can do — structure allows player choices to actually matter.

Our narrative world model is crafted to provide that structure. We use our human expertise to build a scaffolding that facilitates real character development and narrative payoffs for player choices. The outcome is a story that feels like a story.

Seasons, Episodes, and Scenes

We divide our story scaffolding into three nested tiers, like story matryoshka dolls: Storylines, Arcs, and Scenes.

Storylines are the largest unit of our story structure. Storylines are at the scale of a novel, or a season of a television series. They’re the overarching plots that span several arcs. From a time-scale perspective, storylines require longer-term investment to make sure they include setup, development, and payoff.

A novel or season of a show (or a Hidden Door world!) often consists of several storylines advancing concurrently. For example, a detective procedural television series might have:

• A storyline where the detective is slowly realizing several seemingly unrelated cases are connected as part of a larger conspiracy.
• A storyline where the detective is in a love triangle with two other recurring characters.
• A storyline where the detective is trying to prove themself to their mentor, a no-nonsense retired Chief of Police.

These storylines aren’t isolated from each other. In various episodes, the detective may have to rescue one of their love interests from the clutches of the conspiracy. Investigating the conspiracy could lead to a cold case that their mentor was never able to solve. And there may be a bottle episode where the detective has to attend an awkward dinner party hosted by their mentor, with both their love interests also in attendance.

Within the narrative world model of Hidden Door, each of those episodes would be an arc. An arc is a series of scenes with a shared premise, or about the same larger event. Arcs are flexible and can vary somewhat in their size and scope — they’re anything that is between a Storyline and a Scene. Storylines are composed of Arcs, and Arcs are composed of Scenes.

The smallest unit of story structure in this hierarchy — though not the smallest unit; after all, beats and lines exist! — is a scene. Scenes are short, unusually staying in one location and involving the same set of characters. A scene is defined by one main event that moves the story forward — a fight, a date, a party. Our culture is full of memorable, iconic scenes: the balcony scene in Romeo and Juliet, Darth Vader’s fight with Luke at the end of The Empire Strikes Back, and the chocolate factory in I Love Lucy.

Storylines, arcs and scenes are all made up of beats, in different ways. Think of a beat as a casting call. The storyline says “hey, I need an arc that can fulfill these requirements” and our system pitches the best arcs, given the requirements of that beat as well as the context of the world and the rest of the story so far. This takes into account things like We offer the top three arc pitches to the player, giving them the final choice of which arc they want to pursue. Arcs go through a similar casting process to cast each of its beats with scenes.

Here’s a simple example. Say we’re playing The First Hunt, an origin storyline in Hidden Door’s Dracula world. In this storyline, the main character starts as a vampire hunter and hunts their first vampire.

As a player, you’ll encounter the Vampire Hunter Origin arc and one of a handful of vampire hunter origin scenes we have hand-authored for this purpose. For the first story in any given world we know the starting conditions, and everything that has happened so far (nothing!). For any given origin Storyline, the world model is likely to use the same arcs and scenes.

Of course, most situations aren’t so simple! While origins have well-defined starting parameters, most situations are less predictable.

In Practice: Love On Thin Ice

This is where the magic happens, and our story systems can really shine. Through combinations of modular storylines, arcs, and scenes, we can provide both satisfying narrative structure — character growth, setups and payoffs, foreshadowing, rising and falling action — along with surprise and flexibility, without railroading the player.

Let’s imagine that we’re playing a character named Samantha who is a star college hockey player in a modern-day setting, and we’re in the middle of a Rivals to Lovers storyline with her longtime foe, Nelly. We’ve already completed the first beat of the storyline, so we’re ready for the second — Guard Down, where Samantha and Nelly are forced by circumstance into close proximity to each other in a situation where they are emotionally vulnerable.

There are a lot of different arcs that could fulfill that storyline beat well! But in this instance, Samantha and Nelly share a mentor, their hockey coach. Perfect! The system offers the arc Begrudging Teamwork, where two rivals are forced to work together by their mutual mentor — in this case, a mandatory weekend at a special training camp to improve the dynamic between the team’s two best players. Their coach sees their potential on the ice, if only they could realize they’re on the same team!

Let's visualize what happens when the player chooses a storyline, the system chooses beats to fulfill, and the characters' established narrative roles shape the story.

The Begrudging Teamwork arc has a beat where the two rivals attempt to work together, but their bickering makes things more difficult. This arc isn’t romantic by default, but since in addition to being rivals Samantha and Nelly have crushes on each other, the Only One Bed scene is available — it turns out their coach only booked one room at the training camp! They’re going to have to get used to being closer than they expected.

We tested this arc by making the story real in-platform and playing through it! Here's a comic (generated using the Hidden Door MCP) that shows a pivotal scene from the origin story. Nelly and Samantha both try to impress their coach, but wind up embarrassing themselves. The story hints at the narrative consequence — the training camp that serves as the next scene — in the final moments of the story.

This single storyline is an example of many, many possibilities created by our story engine. As of writing this blog post, official worlds in our catalog contain 80 Storylines, over 200 Arcs, and over 300 Scenes, for more than 4 million combinations of Storyline, Arc, and Scene. That’s the happy medium between constraint and structure. And those numbers are only counting our hand-authored, in-house content! We’re constantly adding more, and Atlas creators can create their own storylines, too. The best way to get familiar with our story hierarchy is by building a world, so please, give that a try!