How to Play an AI Murder Mystery
Missing Witness gives you two ways to play authored murder mysteries in your browser. In Single Player mode, you are the detective: every suspect is played by AI, and you move through four tabs — Brief, Chat, Clues, and Verdict — before an AI judge scores your theory out of 100. In Multiplayer mode, 2 to 6 friends join a live room via an invite link, each player claims a suspect role card, AI automatically fills any empty seats, and the table progresses through reading, statements, discussion, voting, and the final debrief.
1. Choose a case (Solo or Multiplayer)
There is no set order. Filter the case library by genre and difficulty, or visit the Multiplayer hub if you are playing with friends.
- Each case page shows the difficulty, number of suspects, full briefing, cast, and searchable rooms so you can pick the right mystery before starting.
- For a first solo case, try one rated Easy or Medium, or start with the free case The Womb House.
- To play role-card script murder with 2–6 friends, click Multiplayer in the top bar or press 'Play with friends (multiplayer)' on any supported case page.
Go deeper:Getting Started · How to Play Missing WitnessMultiplayer Mode · How to Play With Friends in a Room
2. Brief: check Your Goal first
In Single Player mode, the Brief tab holds the synopsis, the Case File, and Meet the Suspects. Read it through before you ask anything.
- Your Goal decides what your final answer has to cover: some cases ask you to name a killer, others to uncover a hidden truth, and there may be more than one culprit.
- Meet the Suspects only gives each person's public face. What they are hiding, you have to draw out.
3. Chat: hear the openings, then ask anything
Press Start the Game and each suspect gives an opening statement. After that you type questions in plain words; there is no menu of options.
- Opening statements are prepared stories. Whoever has a time that does not fit, or skips part of the evening, is your first target.
- Ask the group and each suspect decides whether to speak up, sometimes contradicting one another.
- Tap a portrait to @ one suspect and only they answer: the way to press for detail or confront someone with evidence.
- Suspects lie or deflect to protect their secrets. A story that changes is the one to chase.
Go deeper:Interrogation Strategies · Question AI SuspectsGroup Chat Mastery · Control a Crowded Interrogation
4. Clues: search rooms and update your notes
The Clues tab is your notebook: evidence and testimony all end up in your Case Notes.
- Pick a place under Search Rooms and what you find is written straight into your notes.
- Testimony from the chat joins them when you tap Update notes.
- The notes sort events into a Timeline, park anything without a clear time under Untimed Fragments, and mark new entries.
- Gaps and overlaps in the timeline are usually where the case breaks open.
Go deeper:Clue Investigation · Search Rooms & Build a TimelineTimeline Reconstruction · Order Events Like a Detective
5. Verdict: write the whole answer
In the Verdict tab, write your conclusion around Your Goal and press Submit Theory. A name on its own scores little; the judge looks for the chain of evidence, so answer:
- Who did it, or what really happened
- How it was done, and when
- Why
- Why the most suspicious people can be ruled out
Go deeper:Write a Winning Accusation · Scoring & Theory Structure
Scoring and the ending (Single Player)
Once you submit, the AI judge scores your theory against the case's hidden truth, out of 100.
- Every case has its own weighted scoring points, usually covering key identities, method, timeline and motive.
- They only ask for conclusions you can reach by questioning or searching, never pure guesses.
- Score 60 or more and the full case story is revealed; 80 or more counts as solved.
- The Judge's Notes show what you got right and what you missed. To try for a higher score, press Restart to clear the case and play it again.
Go deeper:Replay for Higher Scores · Second-Run Detective Play
Multiplayer Mode: Play Role-Card Mysteries With Friends
In Multiplayer mode (/multiplayer), 2 to 6 friends play inside a synchronized browser room as the suspects themselves — with no human Game Master needed and AI automatically filling any empty seats.
- 1. Open a Room & Invite Friends: The host picks one of the 10 multiplayer cases and opens a room. Only the host unlocks the case; friends join via the invite link for free with just a nickname (no sign-up required).
- 2. Pick Characters & AI Fill-Ins: Each player claims a suspect seat. Any seat left unclaimed is played by an AI character in role, so you can start a 4-, 5-, or 6-seat mystery with as few as 2 humans.
- 3. Read Your Private Role Card: Everyone reads the public prologue and their private card (your story, public cover version, secrets to hide, and personal tasks). If you draw the killer seat, your card tells you so and gives you strategies to survive the vote.
- 4. Simultaneous Statements & Free Discussion: Everyone writes their opening statement at the same time, published together in seat order. In Discussion, question human or AI suspects by mentioning their character name in chat. If a player drops offline for 60 seconds, AI temporarily stands in until they return.
- 5. Final Words, Vote & Full Debrief: Submit your closing argument, vote for the killer on the ballot, and reveal the full truth, task answers, and every character's secret role card.
Go deeper:Multiplayer Mode · How to Play With Friends in a Room
Tips for new detectives
- Start with open questions ("What were you doing that night?") before narrowing in on times and details.
- When two stories conflict, @ each suspect separately with the same question; it shows who is lying faster than the group chat.
- After you find a piece of evidence, take it back to the people it involves. Evidence often pulls out what testimony left unsaid.
- The first person you suspect is rarely the answer. Before you submit, check every suspect for opportunity and motive.
- In Multiplayer rooms, don't read your role card word-for-word — summarize your alibi in your own words, and mention an AI character's name in chat whenever you want to press them.
Go deeper:Red Herrings & Fair Play · Tell Misdirection from TruthDetective Mindset · Fair-Play Reasoning Skills
Frequently asked questions
How many players do I need?
Just 1 player for Single Player detective mode (where AI plays every suspect), or 2 to 6 players for Multiplayer mode (where each friend claims a character seat and AI automatically plays any remaining seats).
How do Multiplayer rooms work? Do my friends need an account or to pay?
The host signs in, unlocks the case, and opens a room at /multiplayer. You copy the invite link and send it to your friends — they join in their browser with a nickname for free, with no account registration or download required.
Do I lose progress if I leave mid-case?
In Single Player mode, chat, searches, and case notes are saved per case in your browser so you can pick up where you left off. In Multiplayer mode, the room state is saved on the server; if a player disconnects for over 60 seconds, AI stands in for their character and hands the seat right back when they reconnect.
What if I get stuck?
Go back to your Case Notes and look for gaps in the Timeline and anything under Untimed Fragments. @ a suspect whose story keeps shifting, or search a place you have not visited yet.
Can I play on my phone?
Yes. Both Single Player mode (Brief, Chat, Clues, and Verdict tabs) and Multiplayer rooms (Table, My card, and Players tabs) are built for mobile and desktop browsers.
Go deeper:Play on Phone & Tablet · Mobile Detective TipsMultiplayer Mode · How to Play With Friends in a Room