ONE FAIR SOLUTION · BY MIKKO L

Murder mystery puzzle book for adults Every clue.
One fair
solution.

Forty murder mystery logic puzzles for adults.
One quiet harbor. A trail of evidence only you can put together.

No guessing. No hidden clues. Just deduction.

COPPER NARROWS · CIVIC ARCHIVE
One Fair Solution by Mikko L, a murder mystery puzzle book with 40 logic puzzles for adults. Cover illustration of a harbor crane.
FORTY CASES01FAIR SOLUTION
THE PAPERBACK EDITION7 × 10 IN.
40 original cases4 difficulty levels3 hints per case1 solution to every case

THE GREAT LAKES · A FICTIONAL HARBOR TOWN

An ink illustration of a harbor crane, a small lighthouse, and still water.
COPPER
NARROWS

OFFICE OF UNRESOLVED CASES / EST. IN FICTION

WELCOME TO COPPER NARROWS

The town keeps
its secrets.
The clues don’t.

At the edge of a Great Lakes winter, Linnea Maki keeps a quiet room in the Civic Archive. She isn’t a detective. She’s the clerk who gets the files that never quite closed.

You get what she gets: a short case, a set of numbered clues, and a logic grid. Match the people, objects, and places. Follow the evidence until only one answer remains.

Everything you need is in the clues.
Nothing you need is hidden in the story.

READ THE CASE. WORK THE GRID. NAME THE KILLER.

A murder mystery book
you can actually solve.

If you enjoy a good whodunit and the satisfaction of a logic grid puzzle, One Fair Solution brings them together. Each of its 40 original cases asks you to work out who killed the victim, what they used, and where it happened. Hard and Expert cases add the hour.

You won’t need outside knowledge or a lucky guess. Every numbered clue belongs to a complete, self-contained puzzle with exactly one solution. Start with an Easy case, use a hint when you need one, and check the step-by-step walkthrough when you’re ready.

Solve a sample case

YOUR FIRST FILE IS READY

Try a free
murder mystery puzzle.

Meet the suspects. Read the evidence.
See if you can close the file.

CASE FILE 001

LATE SEPTEMBER · MUNICIPAL FERRY TERMINAL

The Last Ferry

EASY 01 / 40

The last ferry had cleared the breakwater at eleven. By dawn, the night clerk was dead.

Walt Dennison was found on the terminal floor. Four people had after-hours business in the building. Four objects were logged. Linnea Maki drew a grid and began.

Read the full case

The last ferry to Isle Marin had cleared the breakwater at eleven, and the terminal should have been a box of echoes and wet light. Instead, just after dawn, a sweeper found Walt Dennison on the floor and ran for the harbor master.

By the time the file reached the Civic Archive, the rooms had been cleared and Walt had been taken up the hill. What remained was paper: four names, four rooms, four objects logged out of the building, and a harbor master who wanted the rumor settled before the afternoon paper.

Linnea Maki set the folder square to the desk edge, uncapped her pen, and drew a grid. She had walked past the terminal every workday for nine years. She knew the ticket booth’s sticky drawer, the canteen’s burnt-coffee air, the baggage cage with its chicken-wire shine, and the fuel dock’s rainbow sheen on black water. She also knew Walt: careful with keys, short with late passengers, and kind to the morning bread delivery.

Four people had after-hours business in the terminal. June Harlow, who worked the day window, had come back about a till that would not close. Tomas Reid had been on the dock for a late repair. Priya Shah had left the morning bread and, she said, a word for Walt. Ellis Boone, a harbor pilot held in port by weather, had wanted a key he claimed was his. Linnea wrote the four names down and began.

THE KNOWN FACT

The person who had the boat hook killed Walt Dennison.

FOUR PEOPLE. FOUR POSSIBILITIES.

JH

June HarlowDay cashier at the ferry window

TR

Tomas ReidDock maintenance

PS

Priya ShahDelivers bread to the canteen

EB

Ellis BooneHarbor pilot, held in port by weather

THE EVIDENCE

0 / 6 reviewed

Click a clue to mark it as reviewed.

YOUR DEDUCTION DESK

INTERACTIVE

One person. One object. One place.
Use the clues to find every match.

People and objects logic grid
× Not a match● A match↻ Click to cycle

Each cell cycles: blank → × → ● → blank. Your marks stay in this browser.

A nudge, not a spoiler.

Three hints, one step at a time.

    READY TO CLOSE THE FILE?

    Make your accusation.

    Who killed Walt Dennison, with what, and where?

    Reveal the solution & walkthrough

    CASE CLOSED

    Ellis Boone.
    The boat hook. The baggage cage.

    1. June has the brass key. June is in the ticket booth (1). The key can’t be in the baggage cage or at the fuel dock (3). It can’t be in the canteen, because the coffee pot is there (2).
    2. Ellis is in the baggage cage. He isn’t in the canteen or at the fuel dock (4), and June is in the ticket booth.
    3. Tomas is at the fuel dock with the mooring line. Priya isn’t at the fuel dock (6). With June and Ellis placed, that leaves Tomas. The line is at the fuel dock (5).
    4. Priya is in the canteen with the coffee pot. That leaves the boat hook with Ellis in the baggage cage. The known fact identifies the killer.

    THERE’S MORE IN THE ARCHIVE

    40 logic puzzles.
    Four levels of mystery.

    Start with four suspects.
    Work your way up to six.

    01

    Easy

    8 cases · 4 people

    Objects & places
    02

    Medium

    12 cases · 5 people

    More people. More possibilities.
    03

    Hard

    12 cases · 5 people

    Add the hour to the evidence.
    04

    Expert

    8 cases · 6 people

    Either-or clues. Chains of hours.

    Room to think.

    Large logic grids, space for notes, and an accusation box for your final answer. Made to be worked in pencil.

    Help on your terms.

    Three hints for every case. Full walkthroughs name the clues they use, so you can follow every deduction.

    A fair way to solve.

    Every case stands on its own. Exactly one solution to each, computer-verified. All the evidence is on the page.

    One Fair Solution paperback: 40 murder mystery logic puzzles for adults by Mikko L

    YOUR NEXT CASE IS WAITING

    A pencil.
    A quiet evening.
    One fair solution.

    One Fair Solution by Mikko L
    A Murder Mystery Puzzle Book of 40 Logic Puzzles for Adults

    PAPERBACK7 × 10 IN.ENGLISH2026 EDITION

    Forty original mysteries. One paperback. Your next case starts here.

    ABOUT THE PUZZLES

    What is a murder mystery puzzle book?

    A murder mystery puzzle book gives you cases to solve yourself. In One Fair Solution, each case combines a short fictional crime story with numbered clues and a logic grid. You match suspects to objects and places, then use the known fact to identify the killer. Unlike reading a mystery novel, you make the deduction before checking the answer.

    Is One Fair Solution a puzzle book for adults?

    Yes. One Fair Solution is a murder mystery logic puzzle book for adults, with 40 cases ranging from Easy to Expert. The first eight cases introduce four-person grids. Later cases add more suspects and the hour, building up to six-person Expert puzzles.

    Can I try a murder mystery puzzle for free?

    Yes. Play The Last Ferry, the free interactive first case, on this page. It includes all six clues, three logic grids, progressive hints, and an accusation form. If you want to see how the deduction works, you can reveal the full walkthrough.

    Do I need to read the cases in order?

    No. Each case is a self-contained investigation. Read in order to follow the town from late September into April, or open any file. The final case has all the clues you need, too.

    Are these traditional logic grid puzzles?

    Yes. Each person has exactly one value in each category, and no two people share a value. Use the numbered clues to match people, objects, and places. Hard and Expert cases add the hour.

    Is Copper Narrows a real place?

    No. Copper Narrows, its people, and the Office of Unresolved Cases are fictional. These are invented mysteries designed to be solved through logic.

    What if I get stuck?

    The book includes three progressive hints and a full answer with a step-by-step walkthrough for every case. The interactive first case above includes those same kinds of help.

    A CLEAN SHEET

    Reopen the case?

    This clears your grid marks, reviewed clues, hints, and accusation for Case 01.