Murder mystery sudoku, explained: where the craze came from and where to go next

What a murder mystery sudoku is

It is a logic puzzle that welds together two things you already know: the sudoku grid and the interrogation scene of a crime novel. On a floor plan split into rooms — a beach, a museum after closing time, a Paris flat — you place the suspects following one sudoku rule: one per row and one per column, never repeating.

Each suspect leaves a single line saying where they were or what they saw, and every one of them is telling the truth. With those lines, and nothing else, the board has exactly one possible arrangement. Whoever ends up alone with the victim is the murderer.

There is no luck and no need to guess: you deduce, exactly as in sudoku, except the deduction is made of names and places instead of numbers. Which is why almost everyone describes it the same way: sudoku with Cluedo inside.

Where the craze came from: Murdoku

The genre has a culprit with a name. Murdoku is the work of Manuel Garand, a Canadian puzzle maker based in Montreal whose puzzles have appeared in the Financial Times. The first book came out in October 2025.

In the United States and the United Kingdom it is published by Hachette and Penguin, it is a USA Today and Publishers Weekly bestseller, and there are already three volumes, the latest being Around the World.

Spain is where the figures are clearest. By July 2026 the Spanish press was reporting 17 printings and 300,000 copies sold in Spanish, plus the number one non-fiction spot at Sant Jordi, the country's biggest book day. By August, bookshops were running out. Its editorial director argued it was not a seasonal fad but «a category with a lot of room to run». On social media the #murdoku hashtag has piled up millions of views, and it started with Spanish-speaking creators solving cases live.

For a sense of the ceiling here: Murdle, the crime puzzle series from the same publishing family, passed three million copies across thirty countries. This is not a niche.

Why it hooks people

There is a boring explanation and a good one. The boring one is timing: it arrives in the middle of the screen-fatigue backlash, and a puzzle book is the exact opposite of the scroll.

The good one is that a case is a perfect unit. It starts and it finishes, it lasts about as long as a coffee, it cannot be brute-forced, and when it falls it falls whole: there is an exact moment when two lines cross and the board takes itself apart. That is what brings people back, and it is the same thing that brings people back to sudoku — except here there is also a body.

And it is a genre that gets on unusually well with paper. You solve it in pencil, you cross things out, you back up, you leave it half done on the bedside table and pick it up the next day. Which is why the place it exploded was bookshops.

Sudoku Detective: the book

If the genre already has you, here is ours — and it starts on paper. Sudoku Detective is a book: a full-colour paperback in which every case comes with its solution explained step by step, not merely given. The settings run from the savannah to a museum after closing time, from a dig in Egypt to a Paris flat, each with its own drawn floor plan, and the difficulty climbs as you go.

The cases in the book are its own: they are not on the website. It is a book to keep, to take anywhere and to solve in pencil, which is how this game feels best.

Around the book there is a website where you play free, in the browser, on a phone or a computer, with no sign-up and nothing to download. New cases arrive every week, there are progressive hints for when you get stuck — they give you the next step of the reasoning, not the answer — and some cases have solutions explained on video. It is the place to try the genre before taking it to paper, and to keep playing between books.

Printable cases, free and with no sign-up

And for pencil players who would rather not wait for anything, there are printable cases, free: each one in colour, in black and white — the one people actually print at home, because it does not eat the ink — and with the solution as a separate PDF, so you do not see it by accident.

The solution is not just the answer: it comes with several floor plans, one per batch of steps, and the reasoning written alongside, so you can see why the case works out. They exist in all seven languages of the site and they were made separately: they are not on the site or in the book either.