The fateful note came just as Lenox was settling into his armchair after a long, tiresome day in the city. He read it slowly handed it back to Graham, and told him to throw it away. Its contents gave him a brief moment of preoccupation, but then, with a slight frown, he picked up the evening edition of the Standard and asked for his tea.

It was a bitterly cold late afternoon in the winter of 1865, with snow falling softly over the cobblestones of London. The clock had just chimed five o’clock, and darkness was dropping across the city-the gas lights were on, the shops had begun to close, and busy men filled the streets, making their way home.

It was the sort of day when Lenox would have liked to sit in his library, tinkering with a few books, pulling down atlases and maps, napping by the fire, eating good things, writing notes to his friends and correspondents, and perhaps even braving the weather to walk around the block once or twice.

But alas, such a day wasn’t meant to be. He had been forced to go down to the Yard, even though he had already given Inspector Exeter what he thought was a tidy narrative of the Isabel Lewes case.

It had been an interesting matter, the widely reported Marlborough forgery-interesting, but, in the end, relatively simple. The family should never have had to call him in. It was such a characteristic failure for Exeter: lack of imagination. Lenox tried to be kind, but the inspector irritated him beyond all reason. What part of the man’s mind forbade him from imagining that a woman, even as dignified a woman as Isabel Lewes, could commit a crime? You could be proper or you could investigate. Not both. Exeter was the sort of man who had joined the Yard partly for power and partly because of a sense of duty, but never because it was his true vocation.