In 1920, Inspector Smythe from Scotland Yard visited the retired Sherlock Holmes at his home in Sussex Downs.
“Mr. Holmes,” said Smythe, “your assistance is required in resolving a threat to his majesty, King George.”
Holmes nodded. “Tell me of this threat.”
“We received word from an informant, telling us that an assassin had been hired by a foreign power, charged with killing the king. A few days later, a known foreign agent was arrested while attempting to bribe one of the servants at Buckingham Palace.”
“If you have arrested the man, why do you need my help?” asked Holmes.
“That’s just the thing,” said Smythe. “My superiors are convinced they have ended the threat to the king, but I’m not certain whether this man is the real assassin.”
“What is the man’s name?” asked Holmes.
“Klaus Ng — his father was a Chinese diplomat who married a German girl.”
Holmes frowned. “You said he was a known foreign agent. Certainly not for the Chinese?”
“No,” said Smyth, shaking his head. “He works for the Soviets. He is one of Lenin’s loyal followers — they met while Lenin lived in Munich.”
Holmes smiled. “Yes, it all makes sense now. He is not the real assassin — you must return to London and carry on the hunt.”
“But how can you know?” asked Smythe in astonishment.
“By simple deduction,” said Holmes. “From the information you’ve given me, it is obvious that the man you have captured is a Red Herr Ng.”