Players travel through the streets & alleys of Victorian London picking up clues while attempting to solve 200 intriguing Sherlock Holmes adventures written especially for this game.

The game can be played competitively by 2 or more individuals or teams. Or it can be played as a cooperative game, with all players teaming up as Baker Street Irregulars to help Holmes solve the case. When played this way, the group bands together to decide which of the fourteen locations to visit first, and the meaning of each clue is discussed by the group. (The game can also be played solitaire.)