Mystery logic puzzles you can play free
Mystery logic puzzles are whodunits you solve with reasoning alone: a few suspects, a few facts, and exactly one answer that fits them all. You can play them free online right here. Below are three original mini whodunits with the Fibberson family, drawn as small rooms, each answer hidden until you tap to show it. Then play a full one: Lie of Sight has a new free case every day.
What a whodunit logic puzzle is
A whodunit logic puzzle gives you a small crime, a few suspects and a handful of facts. Unlike a mystery novel, it plays fair: every fact you need is on the page, and exactly one answer fits all of them. You solve it by ruling things out, not by guessing who looks shifty. The best ones are short enough for a coffee and leave you sure of the answer, not just hopeful.
Free whodunit puzzles online: three to try
Each one is a small room seen from above, with the Fibberson family. The rules you need:
- Dad sees his whole row and column.
- The Kid sees his row and column too, but low things like the vase and the sofa block him. He can crawl under a sofa, and the others still see him there.
- Grandma sees two squares in all eight directions.
- Rex the dog can’t see, but smells the eight squares around him, even through walls and furniture.
- Walls and tall things (the bookshelves, the clock) block everyone’s view. People never do, and nobody stands on a prop.
- Exactly one person is lying. In these three, whoever did it is the one fibbing, so catch the liar and you’ve caught the culprit.
In the daily game itself, the story is only scenery: you’re not finding who did it, just who’s lying about what they saw.
Whodunit 1: who ate the cake? (easy)
Someone ate half of the cake. Whoever did it is fibbing.
Dad “I saw the cake.”
Grandma “I saw Rex.”
Rex “I didn’t smell the cake.”
Who did it? Work out who is fibbing: where could everyone be standing so that every story but one is true?
Show the answer
Rex is lying.
Rex is already standing, so check him first. He can’t see, but he smells the eight squares around him, and the cake is on one of them. So “I didn’t smell the cake” can’t be true wherever anyone else stands. A story that fits nowhere belongs to the liar: Rex ate the cake.
The other two fit together. Dad sees straight up his column to the cake, and Grandma, standing just below Rex, sees him.
Whodunit 2: who knocked over the vase? (medium)
Someone knocked over the vase. Whoever did it is fibbing.
Dad “I saw Grandma.”
The Kid “I saw Grandma.”
Grandma “I didn’t see the vase.”
Who did it? Work out who is fibbing: where could everyone be standing so that every story but one is true?
Show the answer
Grandma is lying.
Start with Grandma’s story, then test it. Dad is boxed in: bookshelves above and below him, and a third that ends his row after two squares. He can see only those two squares. The Kid’s column stops at the clock and his row at a bookshelf, so he can see only four squares.
Every one of those squares is right beside the vase, and Grandma sees everything beside her. So if Dad or the Kid is telling the truth, Grandma saw the vase. If she were honest, they would both be lying: two liars. Only one person lies, so it’s Grandma. She knocked over the vase.
One way it works: Grandma on the square where Dad’s and the Kid’s views meet, two along from Dad and two up from the Kid.
Whodunit 3: who kicked the ball into the corner? (harder)
Someone kicked the ball into the corner. Whoever did it is fibbing.
Dad “I saw the Kid.”
The Kid “I didn’t see the ball.”
Grandma “I saw the ball.”
Rex “I smelled the Kid.”
Who did it? Work out who is fibbing: where could everyone be standing so that every story but one is true?
Show the answer
The Kid is lying.
Start with Dad, who is the most boxed in. Bookshelves close his row on both sides and his column above, so the only square he can see is the sofa below him. If he saw the Kid, the Kid is under the sofa.
Now Rex. He smells the eight squares around him, but only two of them are free for the Kid: the square above the ball, and under the sofa. From either one, the Kid looks straight along to the ball. People never block a view.
So if the Kid is honest and didn’t see the ball, he is on neither square, and Dad and Rex are both lying: two liars. Only one person lies, so it’s the Kid, hiding under the sofa. He kicked the ball into the corner.
Deduction puzzles for adults
Deduction puzzles for adults don’t have to be long. What makes one grown-up is that it trusts you: no hints in the wording, no trick question, just facts that only fit together one way. A full Lie of Sight case is bigger than the whodunits above, with four of the family in a furnished room, and most take 2 to 5 minutes.
If you like a longer climb, the free Tricky Cases are harder than the Case Files. More on that in logic puzzles for adults.
Detective logic puzzles
A detective logic puzzle puts you in the detective’s chair: you hear what each witness says, and the case turns on one statement that can’t be true. That is Lie of Sight in a sentence. Every witness says what they saw from where they stood, and you test each story by moving them around the room, until the one that breaks is plain to see.
For the method step by step, see find the liar puzzles.
Murder mystery logic puzzles, without the murder
Most mystery logic puzzles online are murders: Murdle, Murdoku and their cousins, compared in games like Murdle and daily mystery games. Lie of Sight keeps the logic and leaves out the body. Nobody is hurt; someone just ate the cake. It makes a gentler puzzle to share with the family, and the deduction is every bit as strict.
Play a full one
Today’s case is free, with no sign-up, and the same for everyone, so you can compare notes with friends afterward. When you want more, start the free Case Files: 28 free cases: 3 practice, 15 Case Files and 10 Tricky Cases, to play any time.
Questions people ask
What is a mystery logic puzzle?
A whodunit you solve by reasoning alone: you get a few suspects and some facts, and exactly one answer fits all of them. Nothing is left to a hunch, and the clues are enough to prove it.
Where can I play whodunit puzzles online for free?
Lie of Sight has a free find-the-liar case every day in your browser, plus 28 free cases: 3 practice, 15 Case Files and 10 Tricky Cases. For other free daily mysteries, from Murdle to Daily Murder, see our list of daily mystery games.
Is Lie of Sight a murder mystery?
No. It is a cozy family puzzle with no murder in it. You’re not finding who did it, just who’s lying about what they saw.
Ready for today’s case?
A new case every day. Free, with no sign-up to start.