The Baker Street Casebook

Step into Victorian London as Dr John Watson: observe the scene, question witnesses, and build an explanation alongside Sherlock Holmes.

Begin with their first meeting in A Study in Scarlet. Explore illustrated scenes, question witnesses, and connect testimony with physical evidence in your notebook. Different cases bring different puzzles: turn an object to examine it, reconstruct a sequence of events, test a witness's explanation, or trace clues across the London investigation desk in The Sign of the Four. Play with a mouse or touch controls, with hints available when you want them. Return to 221B between cases as Watson's casebook grows.

Play A Study in Scarlet through its ending for free, with no time limit or replay limit. A one-time purchase of US$9.99 unlocks the stories beyond it and includes future regular story updates as they are released.

The current build contains 12 playable canonical cases, including A Study in Scarlet, The Sign of the Four, and The Noble Bachelor. A further 48 canonical cases are planned and marked as forthcoming in the game. These planned cases are not playable yet.

English is the default language; Japanese is also available. Play in a browser on a computer or smartphone. Progress is saved on your device, with save-file export and import for moving or backing up your casebook.