Three complete puzzles on this page, all from a detective case file: one 3×3 logic grid and two coded notes. Every answer is below the puzzle it belongs to, including the reasoning. Hit Ctrl+P (Cmd+P on Mac) if you want them on paper. No download, no email, no sign-up.
Three detectives caught three suspects. Each suspect owns exactly one pet and drives exactly one vehicle, and no two match. Work out who owns what from the four clues.
| Cat | Hamster | Parrot | Scooter | Truck | Van | |
|---|---|---|---|---|---|---|
| Detective Ana | ||||||
| Detective Ben | ||||||
| Detective Cal |
Question: for each detective — which pet owner did they catch, and what does that detective drive?
Ana owns the cat and drives the truck. Ben owns the parrot. Cal owns the hamster and drives the van.
Reasoning: clue 1 gives Ana the cat. Clue 2 puts Ben in the scooter. Clue 3 needs a van-driving detective who caught the parrot owner; Ben drives the scooter and clue 4 keeps Cal off the cat owner (already Ana's), so the van belongs to Cal. That leaves the truck for Ana. Clue 3 then puts the parrot with Ben, leaving Cal the hamster.
A coded note was found in the suspect's desk. The hint: each letter was shifted forward through the alphabet by the same amount, and spaces stayed where they were. Decode it.
Decoded: THE GUILTY PARTNER FLEW NORTH AT DAWN (shift 7).
Method: short words give the shift away. The two-letter word AOL appears once, and a two-letter word shifted by the same amount every time is a good anchor — try shifts until AOL becomes a real word: a shift back of 7 turns A→T, O→H, L→E, giving THE. Apply 7 to the whole line.
A second note used a substitution: A becomes Z, B becomes Y, C becomes X, and so on through the alphabet (each letter mapped to its mirror). Decode it.
Decoded: THE THIEF KNEW THE ALARM CODE ALL ALONG.
Method: with Atbash you can decode from either end — the cipher alphabet is the plain alphabet reversed. G is the 7th letter from the start, so it becomes the 7th from the end: T. S (19th) mirrors to H, V (22nd) mirrors to E. GSV = THE, and the rest follows the same swap.
one-time · 20 logic grids, 15 ciphers, 10 witness matches, 10 timelines, 5 final cases · full keys + reasoning · A4 + US Letter PDF