Play online now, free The 4 books Contact
A1
The hall

Everyone tells the truth.One of them kills.

A floor plan, some suspects and their statements. Nobody lies: there is only one way to place them all.

Play six cases Download and print
  • One single solution
  • You never have to guess
  • Every solution, reasoned step by step
A case page: the statements on the left, the floor plan on the right
A case, exactly as it is printed
B2
The library

4 books, 320 cases

Eighty cases per volume across twenty settings, ordered by measured difficulty and explained step by step.

Cover of Nobody Lies
Volume 1

Nobody Lies

Twenty houses, a body in each. The book that opens the series and teaches you to read a floor plan.

Buy it on Amazon
Cover of the Christmas special
Special

Nobody Lies at Christmas

Snow closes the road, the house fills with guests, and someone does not make it to Christmas Eve.

On Amazon in November
Cover of Nobody Lies on Board
Volume 2

Nobody Lies on Board

Trains, ships, planes and submarines. Nobody gets off until it is solved.

On Amazon in December
Cover of Nobody Lies Far from Home
Volume 3

Nobody Lies Far from Home

Twenty houses around the world, each shut in for a different reason: the monsoon, the ice, the flood.

Coming soon
C3
The evidence room

Five more cases, and a new one every week

I send you five cases that are in no book: two easy, two medium and one hard, with the solutions explained step by step. After that, a new case every week. No other emails than those.

Three free cases, ready to print

Six pages: the rules, one easy case, one medium and one hard, with their solutions explained. No sign-up. Choose a language:

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D4
The archive

Why these and not others

ONE

One single solution

Every case has been checked by two different programs and by brute force. There are never two possible answers, and no step requires guessing.

TWO

The why is explained

The solution is not a filled-in grid: it is the whole reasoning, step by step, saying which statement forces each move.

THREE

No clue is translated

Statements are written from each language's own grammar. No sentence is ever translated, so no translation can make a case unsolvable.

A case solution: the solved grid above and the step-by-step reasoning below
The solution, reasoned out
E5
The study

Tessa Dalmer

Crimes solved with a pencil: no forensics, no alibis, no hunches.When everyone tells the truth, there is only one place left for each of them.

Contact

A case you cannot crack? A typo? Want to review the book or translate it into your language? Write to me and I answer myself.

hola@tessadalmer.com