Published by Daniel Jenkins for 5 Minute Detective. How we make the site.
A fair mystery gives you the clues before the answer. See how a few extra facts turn a guessing game into a puzzle you can solve.
A fair mystery gives you a way to work out the answer before you open it. It can still be hard and surprising. But the answer must use facts you could already find.
These checks can help you solve a puzzle or write your own. Our About page explains how we make and publish the site.
Give the player the facts in time
A clue can be easy to miss. It may also seem to mean more than one thing. But the player must be able to find it before choosing an answer. This includes special facts about a clock, lock or relationship.
Make it clear which details come from the scene and which come from a suspect. A character may lie. The final explanation should not quietly change facts the story already gave you.
- Give any special facts the answer needs, such as how a lock works.
- Keep the same rules about places, times and objects throughout.
- Make sure the clues lead to the answer.
- Explain why the strongest other answer does not fit.
Example: the missing club stamp
An early draft says a club stamp vanished between 18:00 and 18:20. Ada, Joel and Noor each visited the room during that time. The answer names Joel because he went in at 18:12. But all three had a chance. That fact alone cannot pick Joel.
Now add two clear photos of the open drawer. At 18:11, the stamp is there. At 18:15, it is gone. A video records every visit through the door. All the records use the same correct clock.
Scroll sideways in the table to read every column.
| Visit or check | Time | What it tells us |
|---|---|---|
| Ada visits | 18:08–18:10 | She leaves before a photo shows the stamp still there. |
| A photo shows the stamp in the drawer | 18:11 | The stamp is taken after this check. |
| Joel visits | 18:12–18:14 | He is in the room between the two photos. |
| A photo shows the empty drawer | 18:15 | The stamp is already gone. |
| Noor visits | 18:16–18:18 | She arrives after the stamp is gone. |
We also need clear rules. This room has one entrance, and the video watches it the whole time. Nobody else is inside. The stamp can only be taken by someone in the room. With these facts, only Joel could have taken it between the photos.
We can now ask, “Who took the stamp?” We cannot yet ask why, or whether they had permission. An answer such as “Joel stole it out of jealousy” would add facts we have not been given.
Try another answer
Check the same clues with another suspect in mind. Ada left before the stamp was last seen. Noor arrived after it was gone. Neither could have taken it during their visit. This is why Joel fits and the other two do not.
You do not need to explain away a secret twin or an extra door the story has ruled out. But if another answer fits all the given facts, the puzzle needs more work. Add a clue that tells the answers apart, or ask a less certain question.
Make it clear as well as fair
A simple puzzle can be fair. A harder one can also be fair if the player has all the facts needed for its steps. Small print, unclear times or a surprise technical trick only make the clues harder to use.
Check how the clues look on a phone. Is an important line easy to find? Are the labels clear? Can the reader see the detail in the picture? Add a written description when it helps explain a visual clue.
Ask a fresh reader to try it. They may spot a gap the writer has missed. Automated checks can find missing fields or broken links. They cannot tell you whether a person understands the clue. Say what was actually checked when you describe a review.
Try it: a clock detail revealed too late
A puzzle asks who moved a notebook at 20:00. Two suspects use different clocks in their accounts. Only in the answer do you learn that the wall clock was ten minutes slow. You need that fact to choose the right person, but no earlier clue gives it.
Why is this unfair? What clue could you add without simply naming the answer?
Show the answer and explanation
The player needed a fact that the puzzle kept back. Learning it in the answer explains the writer's choice. It does not give the player a fair way to make that choice earlier.
Show both clocks at the same moment before the player decides. Also say whether the gap between them stays the same. Then check that the changed times really tell the suspects apart. This clue helps only if the rest of the puzzle also fits.
Things to remember
- Give the player every fact and rule needed before they choose.
- Ask only what the clues let the player work out.
- Try another answer and check it against all the rules.
- Check the logic, the wording and the page layout. Be clear about what was reviewed.
Use the facts in the story. If something is still unknown, leave it as a question.