About this game
Play Signal Room, a free online detective game: interview four witnesses, inspect records and prove which alibi is false. Six original fictional mysteries turn clocks, ferry routes, document dates, photographs, mechanical evidence and backup timestamps into short investigations. Each file has eight written statements, four records and a fixed explanation. Switch between witnesses, ask visible questions or use topic matching to locate a reply, then select the exact statement and the independent record that contradicts it. The game never labels the culprit for you just because you opened a clue. Wrong submissions give you another chance without deleting your interviews, and two optional nudges can help you find an overlooked detail. Every case is available in the archive, while the daily UTC selection rotates through the same six-case collection. Progress is stored on this device, and shared case links preserve the case without revealing its culprit or proof. This is a written, rule-driven mystery game: it does not connect you to a live person or a generative chatbot. All game logic works locally without an API key or model usage charges.