The Blackout in the Spa at the Grand Hotel
Today's case · Easy · 6×6Free in the browser, new every day at midnight UTC
He was on an armchair. He was in the Restaurant.
Pick a suspect, then tap a cell.
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What makes it a fair mystery
A good murder mystery riddle gives you everything you need and then dares you to see it. Many riddles break that promise: the answer turns on a word with two meanings, a fact the story never mentioned or a twist the author kept in a drawer. A murder sudoku case cannot cheat that way, because it is a logic puzzle first.
Every clue is a plain fact about one person: "He was in the Library." "She was beside a plant." "He was not in the top row." Every clue is true. None is decoration, and none is a trick of wording. The board itself adds the rest: no two people share a row, no two share a column, and the victim was alone in a room with exactly one other person.
Before a case is published, a solver checks two things. First, that only one arrangement of people fits every clue. Second, that you can reach it by reasoning alone, one deduction at a time, without trying a placement and backing out when it fails. So when you finish, you have not guessed the murderer. You have proved who it was.
How to solve one
- Read every clue once before you place anyone. Some clues say a lot, like a room or a row. Others only rule things out. Know which is which.
- Start with the clue that leaves the fewest squares. A person in a small room, or in a corner, often has only one or two places to stand. Place them first.
- Close the row and the column. Each time you place someone, nobody else can use that row or that column. Cross them off for everyone.
- Look for the last free square. When a person has one square left, or a row has one person who can still fit in it, that is a placement.
- Use the negative clues late. "She was not in the Kitchen" seems weak at the start. Near the end it is often the clue that finishes the board.
- Find the room with the victim. Exactly one other person shares it. That is your killer.
Stuck? Mark the squares you have ruled out and look again at the person with the fewest options left. The full list of rules is on the rules page, and the techniques guide walks through the patterns that come up again and again.
How long a case takes
The daily case changes size through the week. Early in the week it is a small board with five or six suspects, a few minutes over coffee. Later in the week the board grows and the clues get quieter, so a case can take twenty minutes or more. Each case shows its level and size above the board, and nothing is timed: you can leave it and come back.
Where to find more cases to solve
A new murder appears every day at midnight UTC on the daily case page, the same one for everyone. Past cases stay in the archive, each with a step-by-step solution once its day is over, so you can work through them at your own pace or check how a deduction should have gone.
If you prefer pencil and paper, the printable cases come in three levels, with the solutions on a separate page. Every case happens somewhere, and the settings and casts page groups the cases by place, from a manor house to a lighthouse. New to the format? How to play takes two minutes.
Each kind of statement has its own exact meaning. The clue types page explains every one, with an example board.
Put it to work on a real case
A new murder at midnight UTC, free in the browser, with one arrangement that fits every clue.