Casebook: A Study in Pursuit

One mystery a week. One warrant. No second chances.

Something has been stolen, and the thief is ahead of you — booked out of England on tomorrow's boat-trains. Read the testimony, choose which district to chase into next, and spend your hours well: witnesses steer, they never spell it out, and a wrong turn costs real time off a clock that really runs out.

• Follow the trail. Every clue points somewhere — if you read it right. The cab that smelled of hops, the torn directory page, the first train after ten. Nothing is labeled; everything is knowable.
• Narrow the registry. Six names from Scotland Yard's files. Every clue fits three of them; every pair still fits two; only all of them together name one. Strike the cards yourself — the notebook records what was said, verbatim, and never draws your conclusions for you.
• Send the Irregulars. The Baker Street boys will scout one district and report back — if you'll spend the hours.
• Swear the warrant. At the end of the line, name your suspect. Right, and the case closes with the full chain laid bare. Wrong, and they board the train while Lestrade holds the wrong soul by the elbow. Miss the boat entirely and the file reads unsolved.

Every case is built by a constraint engine and machine-verified before it ships: the trail is always completable, the culprit is always provable from the evidence, and the deciding details are always there — buried where only a careful reader finds them. When it's over, the post-mortem shows you exactly what you missed.

A new case lands every Monday. The chase runs through the public-domain London of the Sherlock Holmes stories — the characters of Holmes, Watson, and the Irregulars appear as published in Arthur Conan Doyle's public-domain canon. The films are built from period engravings by Sidney Paget and Gustave Doré; the registry portraits are original illustrations in the same manner. The mysteries themselves are original. This game is not affiliated with or endorsed by any estate or adaptation.

Free to play, in your browser. If a case beats you, Monday is never far away.