That confirmed it. ‘I’m off to pack. Unlock your desk and have my chequebook out, or I shall break open the damned drawer.’ Normally I am a patient man, but perhaps it was the heat.

I was off within the hour, chequebook in hand and the mysterious box tucked safely in an inner pocket of my linen jacket. I would see to finding a locksmith in Bath, far away from prying eyes.

As the train steamed westward that evening, I slid open the window in my first-class carriage and felt the evening air rush in as a cooling breeze. I was relieved to be departing London, and to be honest, Sherlock Holmes.

An image of his thin face when I left, drawn and, dare I say, a bit sad, floated into my brain. Let him miss me, I thought crossly.

It was not one of my finer moments, and one I came to regret.

CHAPTER 3

You Left Me Hanging

Ten days later, even though lowering clouds darkened London with the promise of a summer storm, my mood was light as I returned in a cab from Paddington Station towards Baker Street. My extended holiday in Bath had been restorative. Given Holmes’s disputatious and dismissive mood of late, it was a welcome break to spend time with James Montgomery, a fellow soldier whom I had known in India, and two other comrades, whose ready laughter and playful demeanours had lifted my spirits.

Despite Holmes’s ill-placed concern, I had won a fair amount of money at cards. And while the best locksmith in Bath could do nothing with the mysterious box, I was sure a London expert would soon have it open. And so I had allowed myself to enjoy the baths every day and partook of wonderful cuisine: roast beef, oysters, champagne.

A dense tropical heat blanketed Baker Street. My medical colleagues who still believed in the miasmic transfer of disease were likely to be frantic at this weather.

As my cab pulled up to 221, I glanced up at our windows. The curtains were closed against the morning light, which was muted through a canopy of summer storm clouds. But the windows, too, were closed. That was odd.

Just as I descended from the carriage, the sky broke open and a torrent of rain dumped down as though some mischievous god had upended an enormous bucket on Baker Street.

‘Mrs Hudson!’ I exclaimed, greeting our landlady as she glided into the vestibule. But instead of her usual warm response, she took my drenched hat and coat wordlessly, her face cloudier than the sky outside.

While I may ‘see but not observe’, as my friend so often remarked, it would be difficult for any man to miss her distinct aura of reproach.

‘Dreadful weather!’ I put on my best smile. ‘But it is supposed to break the heat. Good to be home. How are you, Mrs Hudson?’

‘Just go on up, Doctor. It has been a challenging two weeks.’