"We have a new case, Watson!" he exclaimed. "A man is discovered, dead but without a slip of identification upon him, and possessing something of a peculiarly mysterious nature. What more could one ask for on so dull a morning as this?"

London's bylanes are thriving with mysterious murders and baffling disappearances. With spooky shadows lurking around at every corner of the city's most inhabited streets, it is up to the great private detective Sherlock Holmes and his veteran physician friend Dr. John Watson to catch these criminals before they disrupt the city's peace.

When there is no logical explanation in the murder of an old, defenceless woman other than a 'supernatural attack', Holmes and Watson step in to prove every person wrong. When supposed commoners stalk a man who is later found dead, they take charge of the investigation. When Holmes's brother Mycroft urgently calls them to recover an invaluable and oneofakind machine for the government, the duo assure him that they are merely hours away from retrieving it.

The perpetrators of the crimes are at the mercy of the residents of 221b Baker Street.