Logic puzzle books · Grid Mysteries
Grid MysteriesThe Great Detectives
by Milo Carter
80 sudoku-style logic cases for ages 9-12, from 6×6 to 8×8 grids, and a mysterious thief to unmask: the Shadow.
- Ages 9-12
- English
- 114 pages
- Paperback, 8.5 × 11 in, full color
Also onamazon.co.uk★amazon.ca★amazon.com.au★
Direct links to Amazon, no affiliate links. Price and delivery times are shown on Amazon. Ratings checked on Amazon on November 11 and 13, 2026.
In a nutshell
At the middle school, the museum, the train station, the castle, the film studio and the amusement park, one object after another goes missing. In each case, you read the clues, place the suspects and the object in the grid (only one per row and per column) and work out who was alone with the missing object.
Meanwhile, a mysterious thief strikes in all six places and leaves a black card where the stolen object used to be: they call the thief the Shadow. At the end of each file, a special case leads to a witness, and with the six statements you take on the big final case.
Also in other languages
- FRMystères en grille – Les grands détectives5.0/5 · 2 ratings on amazon.framazon.fr →★ Write a review
- ITMisteri in griglia – I grandi detectiveamazon.it →★ Write a review
- ESMisterios en cuadrícula – Los grandes detectives5.0/5 · 1 rating on amazon.esamazon.es →★ Write a review
- DERätsel im Raster – Die großen Detektiveamazon.de →★ Write a review
What’s inside
- 80 cases that get harder bit by bitSix worlds: the middle school, the museum, the station and the train, the castle, the film studio and the amusement park.
- From 6×6 to 8×8 gridsA challenge that grows with your child.
- The Shadow mysterySix Shadow Files to collect witness statements, then a big final case to unmask the Shadow.
- A guided caseThe practice case is solved step by step, so the rules are easy to learn.
- A hint for every casePrinted upside down: search first, peek later.
- Solutions explainedPlus an agent card to fill in and a Great Detective certificate.
Look inside
Pages from the book
Real pages from the book. Tap an image to enlarge it.
How do you solve a case?
1. Read the clues
Each clue tells you where a character was: on a chair, next to a tree, in the schoolyard…
2. Place the tokens
Only one token per row and per column, just like sudoku. Cross out the squares that can’t work.
3. Unmask the culprit
The culprit is the only suspect who was in the same area as the missing object.
Free · no sign-up · a new one every Wednesday
Try a case before you buy
Puzzle of the week: The Teacher’s Pencil Case (ages 6-8, 4×4 grid). The same idea as in the book: read the clues, place the tokens, find the culprit.
Questions from parents
Good to know
Ages 6-8 or 9-12: which book is right?
This book (ages 9-12) goes from 6×6 to 8×8 grids, with 80 cases. For a child who has never played this kind of game, the book for ages 6-8 (4×4 to 6×6 grids) is a good place to start. The book for ages 6-8 →
What if my child gets stuck?
Every case has a small hint printed upside down, and at the end of the book the solutions are explained step by step.
Does it work in the classroom?
Yes, it’s a great game for practicing careful reading and logic. Our free teaching guide for this book (student missions, answer key and diploma) is ready to print. Teachers can also write to us. For teachers →
Is it available in other languages?
Yes, in French, Italian, Spanish and German. Handy for bilingual families, or for practicing logic in another language.
