Voice interrogation as a game mechanic: building SPCTR in a weekend

There’s no game where you can call a suspect, ask whatever you want, and get a real answer. So I built one.

LLMs are unlocking new kinds of game design, but the industry hasn’t caught up. There are experiments like AI Dungeon, studios are researching, but it’s still early. The cost problem will sort itself out. The design problem is harder: what experiences are actually native to these models? I think interrogation is one.

Why investigation games and voice AI

I’m not a board-game expert, but I play a lot. As a crime-novel and neo-noir nerd, I’ve always liked investigation games like Detective or Sherlock Holmes: shuffling through documents, spotting timeline contradictions, cross-referencing witness statements.

I’m also extremely bullish on voice interfaces. Natural-sounding voice is a horizontal, sci-fi-level superpower across industries. I’m currently devoting most of my time to building in this space (more on that soon), and I wanted to explore voice agents through a narrative lens rather than a B2B SaaS one. Interrogation became the obvious core mechanic.

Then there was the UX. Christmas 2025 is when Claude Code went mainstream, along with its cozy terminal aesthetic. Even non-developers suddenly felt a bit hacky, a bit retro, just by typing into a terminal. I leaned hard into that feeling. Green text on black. Commands as the controller.

From a game-design perspective, the terminal is the player interface: the single place where every action is triggered. Pulling logs, interrogating suspects, taking notes. It also works narratively because it’s a diegetic interface. Set in the early 2000s, you play as a technically savvy investigator who has built their own toolkit: IRC logs, VOIP calls, notes. The terminal is both the player interface and the main character’s workspace.

I also wanted audio to set the mood. I wrapped everything in an original soundtrack generated with Suno. Instrumental, MIDI-based, drawing from dark retro synthpop. Melancholic, but it grows on you.

I had all these ingredients: crime investigation, voice calls as the main mechanic, terminal interface, hacker retro vibes. ChatGPT suggested Specter as the main character name. I liked it, turned it into a nickname (SPCTR), and bought the .net domain. SPCTR was born.

How I built the voice interrogation system

The setting: February 2003. You’re a technically savvy investigator whose children attend a private school. Someone has stolen $150,000 from the scholarship fund through social engineering. The police are about to close the case. A nun who knows you “work with computers” asks for help.

You investigate by reading logs and taking notes, but the calls are where the game comes alive.

Interrogations are built via voice agents in Eleven Labs. They’re constrained conversations designed to stay playable and authored while still feeling alive. Here’s how I achieve this structured emergence:

• Each character is implemented as a separate voice agent with its own voice and personality prompt.
• They are bounded: they only know what that character should realistically know. No agent knows “what happened” in full. One knows they were framed. Another knows they lied about timing. Another knows something felt off but can’t prove it.
• Conversations adapt based on context from the player’s investigation: who you’ve already talked to, which logs you’ve read. This context is passed as variables when calling the Eleven Labs API.
• Each agent also has a lightweight situation tree. Certain authored questions act as triggers, switching the agent to more specific responses with a distinct emotional tone. Key questions unlock precise information or reactions.

The rest is just static files

If the core mechanic works with a few lines of code and some prompting, the rest should be even simpler. There’s no backend. No database. No accounts. No state stored on a server. Everything runs in the browser.

The game logic is plain JavaScript. No frameworks, no build step. Just a few small modules handling game state, commands, and calls. The entire game lives client-side and resets on refresh.

The interface is the terminal. xterm.js does most of the heavy lifting. It gives you a real terminal feel out of the box, and a bit of CSS pushes it into CRT territory. Commands are the only way you interact with the game. No menus, no buttons.

All content is just text. IRC logs, server logs, endings: markdown files fetched at runtime and rendered in the terminal. Adding a clue means editing a file, not touching code.

Notes work similar. As characters speak, the game listens for specific phrases. When something important surfaces, a note appears automatically.

The whole game is a static site deployed on Cloudflare Pages. Git push and it’s live.

Play it yourself

The game is live at spctr.net. It takes about 20 to 30 minutes. You’ll need a microphone and headphones.

Let’s see if you can find out who did it. Things are never as obvious as they seem.

I’d love to hear what you think. Feel free to reach out or share your experience.