Build and run a fair AI mystery with a clue sheet

Choose who holds the answer

Author and player notes are not technically protected secrets. If you want to discover an unknown solution, keep the answer outside your chat; an instruction to withhold it cannot protect it once sent. The AI also cannot reliably build evidence around a fixed answer it has never received.

For this fixed case, a facilitator can keep the author sheet and provide the relevant clue when you choose an action. The AI can portray the witnesses and surroundings using that supplied material. The facilitator checks any extra evidence before it enters the case. If you are playing alone and read the author sheet, you are knowingly dramatizing an investigation. If you give the AI only an unanswered premise, treat the result as an improvised mystery rather than pretending its solution was fixed in advance.

Keep only revealed information in the player note. The worksheets below label their author portions, so a facilitator can share the player portion separately.

Player sheet: the empty mount

At 16:40, the Harbor Planetarium's plate P7 is missing from its display mount. Tonight's demonstration starts at 18:00. The plate is valuable to the exhibit, but no one has been hurt. You play Ellis, a volunteer asked to establish what happened and recover it without making an unsupported accusation. The AI portrays these staff members:

Blank suspect record

• Person: [ ]
• Why they interest Ellis: [ ]
• Opening statement, still only testimony: [ ]

Filled suspects

Ada, projection technician

• Person: Ada, projection technician
• Why they interest Ellis: Can remove and service plates
• Opening statement, still only testimony: "I was preparing tonight's demonstration."

Ben, events coordinator

• Person: Ben, events coordinator
• Why they interest Ellis: Wants to use P7 in a promotional photograph
• Opening statement, still only testimony: "I asked to borrow it. I didn't get permission."

Cleo, collections assistant

• Person: Cleo, collections assistant
• Why they interest Ellis: Checks loans and storage
• Opening statement, still only testimony: "I returned the visitor loan at four."

Ellis initially knows only that the mount is empty and that P7 was displayed at 16:00. Available checks include the mount, staff records, the service room and interviews. Asking to inspect a relevant place should reveal its prepared observations; this case does not require a hidden password or a successful dice roll.

Copy this player starter after adapting the roles to your chosen chat. It contains the opening facts, not the author solution:

The facilitator now supplies only the observation or witness fact appropriate to Ellis's next action. A generated reply might still add something unsupported; read it before continuing.

Record a clue before interpreting it

This is a filled player sheet midway through the investigation. It contains spoilers for those particular clues, but not the final recovery.

Blank player clue record

• ID and origin: [ ]
• Observation or testimony: [ ]
• What it establishes: [ ]
• Hypothesis and next check: [ ]

Filled player clues

O1: mount inspection

• ID and origin: O1, mount inspection
• Observation or testimony: Latch intact; curved moisture mark under the rim
• What it establishes: No visible forced entry; moisture was present
• Hypothesis and next check: Service removal? Check the maintenance desk

T1: Ada interview

• ID and origin: T1, Ada interview
• Observation or testimony: Ada says she stayed in the booth after 16:00
• What it establishes: Her account, not a verified location
• Hypothesis and next check: Compare the service sign-out

O2: signed service record

• ID and origin: O2, signed service record
• Observation or testimony: Ada signed out P7 for drying at 16:12
• What it establishes: Recorded removal by Ada
• Hypothesis and next check: Ask where drying takes place

T2: Cleo interview

• ID and origin: T2, Cleo interview
• Observation or testimony: Cleo saw Ada carry a flat padded sleeve toward the service room at 16:14
• What it establishes: Cleo reports a movement, not the sleeve's contents
• Hypothesis and next check: Inspect that room; compare O2

O3: events desk

• ID and origin: O3, events desk
• Observation or testimony: Ben's unapproved photo request remains on the desk; continuous event footage shows him in the foyer from 16:05 to 16:30
• What it establishes: Ben's request is motive to ask, but the removal interval puts him elsewhere
• Hypothesis and next check: Do not convert desire into guilt

Leave "What it establishes" narrow. An intact latch does not prove that no authorized person removed the plate. A padded sleeve does not prove what was inside it. Combine records, objects and testimony before changing a suspicion into a conclusion.

Justin Alexander's Three Clue Rule recommends preparing several clues for conclusions players need to reach. This case adapts that author technique with three prepared leads to the service room.

Author sheet: fixed explanation and evidence paths

Spoilers begin here. Ada removed P7 at 16:12 after noticing condensation beneath it. She put it in the service room's drying cabinet, shelf B, and signed the service register. She forgot the public "under maintenance" card. Embarrassed by the missing card, she initially claims she stayed in the booth, contradicting her signed removal. Ben did not take P7. Cleo carried a different loan to storage. Do not change this explanation to match the player's first guess.

The case timeline is fixed:

Blank author timeline entry

• Time: [ ]
• Event: [ ]

Filled fixed timeline

16:00

• Time: 16:00
• Event: P7 is displayed; Cleo returns a separate visitor loan to storage

16:05

• Time: 16:05
• Event: Ben begins setting up in the foyer; event footage covers him until 16:30

16:10

• Time: 16:10
• Event: Ada notices condensation beneath P7

16:12

• Time: 16:12
• Event: Ada removes P7 and signs it out for drying

16:14

• Time: 16:14
• Event: Cleo sees Ada carry a padded sleeve toward the service room

16:16

• Time: 16:16
• Event: Ada places P7 on shelf B; the cabinet records the insertion

16:20

• Time: 16:20
• Event: Ada returns to the booth without placing the maintenance card

16:40

• Time: 16:40
• Event: Ellis begins the investigation

Prepare three independently accessible leads to the service room: the signed register names the drying destination; Cleo's testimony identifies the corridor; a service-room intake receipt at the maintenance desk lists P7 and shelf B. Losing one conversation does not remove the other routes. The moisture mark supplies an additional reason to ask about maintenance.

Inside the service room, three checks converge on recovery: the cabinet log lists P7 at 16:16; the object on shelf B bears P7's engraved identifier; Ada's drying note describes the condensation. The engraved identifier establishes which object was recovered. The note and moisture mark explain the maintenance motive. Ada can acknowledge the omission once Ellis presents the service record; a confession is not the sole route to finding the plate.

Ben's photo request remains a plausible early suspicion. It has a prepared check, the foyer footage, rather than an endless chain of new accusations. Cleo's loan has a separate inventory number, L2, and a storage receipt at 16:00. Those records distinguish her ordinary task from P7's later movement.

Play from observation to justified resolution

The following exchange assumes the facilitator has released the relevant facts at each step.

The resolution accounts for the object, the timing, the misleading account and the other suspects. It does not depend on Ellis guessing Ada's name early.

When the investigation stalls or a clue contradicts canon

If Ellis fixates on Ben, use the existing footage check. If Ellis cannot find a next action, have Cleo bring the already prepared intake receipt from the maintenance desk: "You asked about where plates go. This might help." It adds an available route, not a new culprit. A gentler hint can ask which record would distinguish removal from borrowing. Give the player the choice of a hint or the full solution.

An incorrect generated reply might say:

Illustrative scene excerpt: Ben produces P7 from his bag. "I broke the mount at 16:25."

That conflicts with the intact latch, signed drying record and fixed custody. Do not accept it merely because it sounds dramatic. Send:

A corrected illustrative continuation is:

Illustrative scene excerpt: The receipt still points to shelf B. Ben remains in the foyer. Ada stands beside the service-room door. The cabinet has not yet been opened by Ellis.

The correction adds a message; it does not erase the mistaken reply. If the next answer repeats the contradiction, stop and re-supply the small set of accepted clues instead of investigating the invented bag. For general repairs beyond this case, use the continuity guide.

Update your manual player sheet after each accepted clue and check new evidence before using it. The roleplay setup template covers the broader opening; roleplay AI chat is a possible place to send an adapted scene message.

Copy a starter or worksheet

These manual notes include the author solution. Share the player starter separately. Keep an unknown answer outside the investigator's chat.