Description taken from Commodore 64/128 version of this game

You are Sherlock Holmes, master detective. Accompanied by your faithful friend Doctor Watson, you've been responsible for unraveling some of the most devious and complex mysteries to have baffled Scotland Yard. A new case has come to your attention and you're eager to solve it.

You're not the only one hot on the trail, though. Your longstanding competitor, Inspector Lestrade, has decided to match wits with you along with Irene Adler. Even Doctor Watson is in on the hunt. Can you be the first to solve the mystery?

221B Baker Street for the Commodore 64 is based on a Clue-style board game of the same name. Gameplay is turn-based and can accommodate up to four players. After selecting characters, each player can opt to read a special coded hint before the case begins.

The game includes more than 20 individual cases on two floppy disks that can be loaded for a unique gaming experience. Players take turns rolling a single die and moving their character on the board with the number rolled corresponding to the number of moves allowed.

When players enter into buildings they can view clues about the case. The object of the game is to identify all the important facts about the case, such as the perpetrator, motive, weapon, location, and so forth, and then solve the puzzle by piecing the clues together for a solution. Each case has at least one fact that must be identified and most of the cases have unique aspects. ~ Kyle Knight, All Game Guide