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29 cases available this month
Three parcels on the scales
The scales recorded only pairs. To find the missing piece, you must separate their weights.
The ticket from the final rehearsal
Three transformations conceal the number of the person who opened the drawer.
Every label was wrong
One sample is enough to reconstruct three deliberately mislabelled boxes.
The six statements on the ballot box
Only one hypothesis leaves exactly three statements true.
Six minutes to return
The culprit had to reach the storeroom and return within six minutes.
The two-light panel
Only one button press leaves the correct light switched on.
The box that went around
A blue marker passes through a rotation and a swap before ending up within the culprit's reach.
The middle shift
A sheet disappears during the second inspection, but the names on the shift list have been erased.
The amber access pass
A colour reveals the origin of an unauthorised copy.
The box with two filters
The box rejected one card colour, while its opening admitted some bags but not others.
The ticket office message
A false instruction arrived with a four-letter code that had been transformed twice before printing.
The second round
Three restorers inspected a display case twice, and the second round reversed an order never written down in full.
The planetarium trolley
Taking a sphere required collecting a key and returning on time through a network of corridors.
The mask exam
The exercise requires whoever hid the mask to tell one truth and one lie; everyone else must tell two truths.
The applause that came earlier
A recording seems to provide three alibis, but one speaker replayed the applause after a delay.
The aquarium lights
The tank turned violet after two changes, and only one control sequence explains the result.
The automaton's tokens
The automaton accepted a tampered bag; two weighing checks reveal which batch it came from.
The three-carriage train
A package disappeared during one carriage manoeuvre, and the final positions alone are not enough.
The model against the current
The boat was meant to reach the lighthouse but ended up in a tunnel: two junctions reveal the sabotage route.
The scenery calendar
A fictional calendar reveals when a trunk was opened. The instruction combines weeks and opening days.
Three points each
The scoreboard ended in a tie. One surviving result reconstructs all three matches.
The incomplete row
An incomplete grid holds the code. No row or column may repeat a digit.
The programme without times
The programme lost its times. The durations reveal when the substitution occurred.
The third domino
Five tiles form a chain. Its first link determines which tile must go in the middle.
Two checks
One digit changed. Two preserved sums identify the column involved.
Exactly three corridors
The map has two branches. Tracing three sections backwards reveals which office the visitor left.
Two statements each
Counting six statements separates one consistent account from two impossible ones.
Seven tickets
A receipt hides its breakdown, and reservations hide their quantities. Two reconstructions identify the same batch.
The three rooms
A stamp identifies the room used. Three people’s positions reveal who could have been there.