In any performance, the key is convincing oneself first, and at that moment, with my fury and frustration welling close to the surface, I could well imagine my finger tightening. My performance certainly convinced Nesbit, whose breath froze completely in his throat; in the end, Kimball O’Hara, too, allowed himself to believe I meant it. He stood, brushed down his clothing, turned his back, and started walking: east towards the border. I eased the hammer down and took a much-needed lungful of air of my own before pushing past the stunned-looking captain.

I kept the gun on O’Hara’s back all the way to the borders of Khanpur, so it could not be argued that he was escaping of his own volition.

And footsore, famished, and exhausted, we made it back to New Fort a good forty minutes before dawn, to find our drugged chuprassi still snoring gently in his corner.

Before we parted, Nesbit caught my elbow and spoke into my ear. “Would you have shot O’Hara?”

I looked at the man’s features, haggard with fatigue but beautiful still, and I saw only Holmes’ face as the door locked him in. The false moustache shifted on my upper lip as I smiled. “If he’d refused? I honestly don’t know.”

I fell exhausted into bed, half dressed, my legs still twitching with the rhythm of the long miles of jog-trot. But as the first wave of sleep came to carry me away, it brought with it a troubling piece of flotsam.

On first seeing O’Hara, I had been struck by the peculiarly open and unshuttered quality of his eyes; now I recalled where I had seen eyes like those before. They had been in the face of a man Holmes had hunted down in the south of France, a man who preyed on gullible women, to whom he appeared an innocent, friendly, open. Up to the moment his hands closed around their throats.

Chapter Twenty-Four

The horrendous clamour of a laden tea tray came through my door what seemed like minutes after I had shut my eyes. I squinted at the white-clad servant from my tumble of pillows, hating him with a deep passion. Him, I would have shot. Joyously.

“His Highness says, the horses will be ready in one hour,” he informed me, and left before I could find my pretty revolver.

I peeled my moustache from the pillow sourly, and went to assemble Martin Russell from the dregs left behind by the night.

After some thought, I thrust the revolver into an inner pocket, just in case.

Afterwards, thinking back, I realised that I had gone six nights with little sleep, my last uninterrupted rest having been the night before Holmes was abducted. Three nights on the road to Hijarkot, a night with Nesbit preparing to be Martin Russell, and two much-broken nights in Khanpur had left me far from sharp-witted.