How to Play a Detective Case File Game: Rules, Scoring and Tips

Last updated: November 2026

This page covers the rules for Clues at Home case files, but the same approach works for most case-file mysteries. If you want to know what a case file game is before you play one, start with how a detective case file game works.

What you need before you start

• The Case File: open it on a tablet, laptop or TV, or print it on A4 or US letter paper. Black and white is fine.
• The Hints and Solution files: keep them closed. They are separate PDFs so you cannot scroll into the answers by accident.
• A pen and paper (or a notes app) for timelines, suspect lists and your answers.
• Time: check the listing. Our cases run from about 30 minutes for the free case to two or three hours for the longer ones, and you can stop at any STOP page and carry on later.

Setup takes a couple of minutes on screen, or about 10 to 15 minutes if you print and lay out the evidence.

The rules, step by step

1. Read the How to Play page and the briefing

Every Case File opens with a short How to Play page, then the case briefing: what happened, where, and what you have been asked to find out. Read it aloud if you are playing as a group, so everyone starts with the same facts.

2. Work through the evidence in order

The case is split into phases, usually three. Each phase adds new documents: statements, letters, reports, timetables, photos, receipts and suspect profiles. Do not skip ahead. Later phases build on earlier ones, and some evidence only makes sense once you have seen what came before.

3. Answer the questions at the end of each phase

Each phase ends with a few questions. Some are multiple choice or fill in the blank, and some ask you to explain your thinking, such as which alibi a document contradicts. The questions only use evidence you have already seen, so if an answer feels impossible, the clue is somewhere behind you.

4. Stop at every STOP page

A STOP page sits between phases. Write your answers down before you turn it. This is what keeps the game fair: you commit to what you know now, before the next phase changes the picture.

5. Use hints only when you are stuck

The Hints file has hints for each phase, from a gentle nudge to a much stronger push. Read one hint at a time and go back to the evidence before you read the next. Hints cost points, but using one is always better than giving up.

6. Make your final accusation

After the last phase, write down three things: who did it, how they did it, and why. If you are playing as a group, agree on one answer, or let each player write their own and compare. The accusation is worth more than any other part of the game.

7. Open the Solution and score yourselves

Only now open the Solution file. It gives the answer to every question, the full story of what happened, how each clue pointed to the culprit, and why the other suspects were innocent. Add up your points, take off any hint penalty and see your Detective Rating.

How scoring works

Scoring is optional, but it makes the evening more satisfying and gives competitive players something to aim for. In our cases:

• Each phase’s questions earn points, with harder questions worth more.
• The final accusation earns the biggest share: who, then how, then why.
• Hints cost points, and the penalty grows the more hints you use.
• Your total gives you a Detective Rating.

Detective Rating	What it means
Master Detective	Near-perfect score with few or no hints.
Sharp Investigator	You solved it and got most of the reasoning right.
Solid Case Worker	You cracked it in the end, with a few gaps.
Rookie on the Beat	Some good catches, but the culprit or motive slipped past you.
Cold Case	The truth stayed buried this time.

How to play with two, on your own or in a group

• Two players: read the documents together, or split them and swap. One of you keeps the timeline while the other tracks suspects. See our guide to murder mystery games for couples for the cases that suit two best.
• On your own: play exactly the same way, at your own pace. Write your answers down before each STOP page so you are not tempted to change them. Our guide to solo detective games has more ideas.
• A group: put the Case File on a TV or print a copy of the key pages, and give each person a job: timeline keeper, suspect tracker, document reader, note taker. Agree on one answer per question, or score as rival teams. For a full evening plan, see how to host a mystery night at home.

Nobody needs to act, dress up or know the answer in advance. Everyone investigates together. If a particular case works better with a host, its listing says so.

Tips for cracking the case

1. Build a timeline. Most cases turn on who could have been where, and when. Times in statements, receipts and logs are rarely there by accident.
2. Check every alibi against another document. A statement on its own proves nothing. Look for the receipt, letter or report that confirms or breaks it.
3. Track means, motive and opportunity for each suspect. A simple grid on paper stops you fixating on the most obvious person.
4. Re-read earlier phases. New evidence often changes what an old document means.
5. Be suspicious of the obvious suspect. The person who looks guiltiest in the first phase is often there to test you.
6. Explain your reasoning out loud. Saying why you suspect someone is the quickest way to spot a gap in your theory.

Common mistakes to avoid

• Opening the Solution file to check one answer. It spoils everything after it.
• Reading the next phase before writing down your answers.
• Skimming. The detail that solves the case is usually small: a time, a name, a date, a word in a letter.
• Refusing hints out of pride and losing the evening to frustration. One hint costs a few points; a stalled game costs the fun.

Frequently asked questions