It was the second Thursday of January 1894 when Lady Penrose of Eaton Place sent a footman to Baker Street with a letter and a small enclosed sum.
"Our second footman, Mr Holmes - James Carstairs, a steady young man of two-and-twenty - was taken ill at our family Christmas dinner on the evening of December the twenty-seventh and died that night. The doctor pronounced a poisoning. Suspicion has fallen upon the cook, whose mince-pies were blamed; she has been with the family fourteen years and is greatly distressed. The household requires a quiet inquiry before the police court is troubled."
We took a hansom to Eaton Place. At the area gate of the Belgravia townhouse a flower-seller's barrow had been set up, the woman with a missing front upper-left tooth and a black wool shawl, calling violets in her tuneful sing-song; she gave us the smallest of nods as we descended. The dinner-room was as it had been left on the night, the table cleared but the silver still on the sideboard, the cook in tearful attendance.