Case File 085 · Narrative and Game Design

How Mystery Games Hide Clues Without Cheating

The techniques mystery games use to hide clues fairly, and a simple test for telling a clever hidden clue from a cheat.

By Murder Book Editorial TeamPublished 16 September 2026Updated 16 September 2026

Mystery games hide clues without cheating by making them visible but not obvious. The information you need is on screen, in a document or in someone's words, yet it is surrounded by other details, placed before you know it matters, or only meaningful once you connect it to something else. That is the difference between a fair hidden clue and a cheat: a fair clue can be found and understood with what the game has already given you, while a cheat depends on information withheld until the reveal. Games such as Return of the Obra Dinn, The Case of the Golden Idol and Her Story hide clues in plain sight, in volume, in connections between details and in testimony. The rules they follow echo principles that detective fiction writers and adventure game designers set out decades ago.

Key takeaways

A fair clue is available before the player needs it and makes sense in hindsight.
Common hiding techniques include placing clues in plain sight, burying them among ordinary details and letting their meaning depend on another clue.
S. S. Van Dine's 1928 rules said the reader must have "equal opportunity with the detective".
Ron Gilbert's 1989 essay warned against arbitrary puzzles and solutions that make no sense.
Games add a problem books do not have: players choose where to look and in what order.

What counts as cheating in a mystery?

Detective fiction writers debated this long before games existed. In Twenty Rules for Writing Detective Stories (1928), S. S. Van Dine wrote that "the reader must have equal opportunity with the detective for solving the mystery" and that "all clues must be plainly stated and described". He also ruled out tricks on the reader "other than those played legitimately by the criminal on the detective himself".

That last idea is the useful one for game designers. Misdirection is allowed when it lives inside the story, such as a suspect lying, a scene arranged to mislead or an alibi that sounds convincing. Misdirection is cheating when the author simply hides a fact from the player that the investigator had.

In his 1989 essay Why Adventure Games Suck, Ron Gilbert made the equivalent point for puzzles: "Puzzles and their solutions need to make sense." He also warned against "backwards puzzles", where the solution is found before the player knows the problem exists.

Our analysis: in a mystery game, a clue found before the question is asked is not necessarily a backwards puzzle. Often it is the point: the player sees something ordinary and only later realises it mattered. The difference is whether the game gives them a way to return to it or remember it.

How do games hide clues in plain sight?

The most satisfying hidden clue is one the player looked at without seeing.

Return of the Obra Dinn (Lucas Pope, 2018) is built on this. As an insurance investigator boarding a ship that returned to port with no visible crew, you work out what happened to the people aboard. In an interview with Game Developer, Pope said he realised during development that "the real fun part would be figuring out who they are", rather than only how they died.

The Case of the Golden Idol (Color Gray Games, 2022) asks players to "observe closely and reconstruct each scene of death", according to its official site.

Our analysis: in games built on close observation, the strongest clues are hidden by attention rather than locked away: a detail of clothing, a position in a room, an object on a table. When nothing is withheld, a missed clue feels like the player's oversight, not the designer's trick.

How do games hide clues in volume?

Another technique is to surround the important detail with many ordinary ones. Mark Brown's 2023 essay What Makes a Great Detective Game? describes investigation-style games whose space is "impossibly large to wade through, and filled with red herrings". His examples include Her Story, which he describes as a database of "700-odd clips".

Volume is fair only if the player has a method for searching it. In Her Story, the method is typing search terms. In a Game Developer interview, Sam Barlow described having "the computer calculate how well connected clips were, looking at how often words were used and which clips were 'easiest' to discover". Writer and designer Emily Short, reporting on his GDC 2016 talk, noted his slide of the spreadsheet he used to track word use.

Our analysis: this is clue-hiding as engineering. The designer controls how discoverable each piece is by controlling the words in it.

How does meaning depend on another clue?

Some clues are visible but mean nothing on their own. A name in a letter only matters once you know who wrote it. A time only matters once you know when someone claims to have left.

Our analysis: this is the fairest way to hide something, because the information is fully present from the start. The player's job is to connect two pieces. It is also the technique closest to real investigative reasoning, which relies on comparing accounts and timelines. See What Is an Investigative Timeline? for the real-world version.

How do games stop players guessing instead of finding clues?

Hiding clues fairly is half the problem. The other half is making sure players cannot bypass them. Brown calls the answer-checking system "the tester", and notes that Return of the Obra Dinn makes you choose identities from the full crew list rather than a short menu, and that "we need to actually establish three correct fates before the game confirms our thinking".

Our analysis: if guessing is cheap, hidden clues stop mattering, because the player can skip them. A fair mystery protects its clues by making the answer space large enough that finding them is the easier route.

Techniques at a glance

Technique	How the clue is hidden	Example	Fair when
Plain sight	Visible but easy to overlook	Return of the Obra Dinn	The scene can be examined again
Volume	Buried among ordinary details	Her Story	The player has a way to search
Dependency	Meaningless until linked to another clue	Contradiction: Spot The Liar	Both pieces are available
Testimony	Inside what a character says	Phoenix Wright: Ace Attorney Trilogy	Statements can be reviewed
Misdirection	A character or scene misleads	Many whodunnits	The deception exists inside the story

How can you tell a clue was hidden fairly?

Based on the principles above, a useful test is to look back after the solution:

Was the clue shown or stated before the answer was required?
Could the player have understood it with what they knew at the time?
Did any misleading information come from inside the story, rather than from the author?
Could the player return to it or record it?
Does the solution make sense in hindsight? Van Dine's rule 15 puts it this way: "the truth of the problem must at all times be apparent", as long as the reader is shrewd enough to see it.

If the answer to all five is yes, the mystery played fair. For endings that reward this kind of play, see What Makes a Satisfying Mystery Solution?. For games that reward close attention, see Games Where Small Details Matter.

Is there an upcoming game that hides clues in testimony?

Murder Book: The Art of Interrogation is an upcoming narrative interrogation game from Gungrounds in Zagreb, Croatia, and its clues sit in the testimony row of the table above. Instead of searching a room, you observe what a suspect says and how they say it. Its press materials name behaviours such as fabrication, avoidance, narrative gaps and emotional leakage.

Development materials show an evidence board where statements are pinned and linked, including one example connecting "I NEVER met her!" and "I had no idea" to a fabricated description of a gun: a dependency clue, where each statement matters mainly in relation to another. Cases are designed for 5–10-minute sessions. Murder Book is in development for PC (Steam) and mobile, with release currently planned for the end of Q2 2027. For more, read How Murder Book Turns Interrogation Into Gameplay.