‘Well… she… she… she’s obviously not the right girl for you! Much too impractical and time-wasting. She’s probably after your money, too.’

‘Thank you for the warning.’ I might have been mistaken, but I thought I saw the corner of his mouth twitch. It wasn’t a smile. It wasn’t even half a smile. He was far too miserly with his facial expressions for that. It was about a quarter of a smile, at the most, but it was there. ‘Though I seem to remember that back at the ball, Mr Linton, you seemed quite convinced of my attachment to Miss Hamilton, in spite of her many defects. If my memory serves me right, it was even you who originally suggested the idea that I might have feelings for her.’

I flushed guiltily.

‘In fact,’ he continued, ‘you seemed quite extraordinarily interested in the subject - and not very pleased by it. Very interested indeed…’

‘I wasn’t interested!’ I snapped. ‘I was being impolite and nosy, which is normal for me!’

‘That is certainly true.’

Wishing desperately to get off this subject as quickly as possible, I made a dismissive hand gesture.

‘Anyway, we weren’t talking about Miss Hamilton! We were talking about your reason for going to the ball!’

‘She was the reason.’

‘No!’

His eyes narrowed another fraction of an inch. Impressive! Together with the miniscule motion of his mouth, this was the closest he had come to having a facial expression since I had known him. He had to be boiling inside.

‘Strange, Mr Linton, how you seem to know my motives and feelings better than I.’

‘Yes it is, isn’t it? But if you don't know them, somebody has to. You went to the ball to confront Lord Dalgliesh. It was you who sent him that letter!’

‘What letter?’ His voice was so smooth, so cool, I could almost have believed he didn’t know what I was talking about. Almost.

‘That letter. It had a lock of Simmons' hair in it, as a sign that his man had been caught. Remember? You cut off a lock of hair from Simmons' head when we were down in the cellar with him. I didn’t understand that at the time, but now I do.’

Silence. Frozen, ice-hard silence from the centre of the arctic wasteland.

His eyes were dark, the dark green-blue of the sea, and totally unreadable. Still, I had a feeling he knew exactly what I was talking about. I, for my part, hovered somewhere between exhilaration, doubt and fear. I had figured it out, finally! I knew who was behind the theft, without a doubt. Everything fit together.

And yet… and yet… it couldn’t be. It was insane. Lord Daniel Eugene Dalgliesh was, by all accounts, one of the wealthiest men of the British Empire. He didn’t have need of petty theft. He had armies at his command, an entire subcontinent under his control. What would he want with one miserable piece of paper?

‘The only thing I don't understand,’ I continued, my eyes lit still by my epiphany, ‘is why the lock? Why send him a lock of hair, not just a simple letter warning him off?’

I expected him to deny it again or to once again be silent. He actually was silent for some time. But then, just as I opened my mouth for the next attack, he raised his chin and said:

‘A letter could have incriminated me. A paper in which I accused him of theft, even in the vaguest terms? He would have found some way to use it against me! A lock of hair on the other hand - that was a message only he would understand. A message that needed no words or signature.’

A wave of cold swept over me. He had admitted it. He had finally admitted it. My exciting theory was no longer just a theory.

‘It can’t be him.’ How come my voice suddenly sounded so small? ‘It simply can’t. I mean… He’s so wealthy. So powerful. And it’s just a piece of paper. It’s not important.’

He regarded me coolly. Not for the first time, I had the feeling that he was assessing me. And not for the first time, I had no idea what the result was.

‘The American Declaration of Independence was just a piece of paper, Mr Linton. It lost us most of our American colonies. In retrospect, do you think it was “unimportant”?’

‘Um… well… no, I suppose not.’

‘Indeed.’

I lifted an eyebrow. ‘The pen is mightier than the sword? Is that what you’re driving at?’

‘It very much depends on the context. I would prefer a sword to fight a duel, but a pen to plan a war.’

He said ‘to plan a war’ as if it were something he did on a regular basis. Looking into his calm, emotionless face, I could believe he did. Another shudder ran down my back. But it was no shudder of revulsion. Oh no. I remembered his powerful body pressed into me, all that tightly contained energy only a fraction of an inch away. What could he unleash, if he wanted to?

More importantly: what would be unleashed when he pitted himself against his arch enemy?

‘Lord Dalgliesh,’ I muttered. ‘Lord Dalgliesh is a thief.’

Before I could blink, Mr Ambrose had crossed the distance between us. He didn’t grab me this time. He just stood very close in front of me, one finger touching my lips. The feeling was electric, sending tingles from my mouth all through my body.

‘Don’t ever,’ he mouthed, ‘say that aloud again. Not ever. Not if you want to live to see your next birthday. Do you understand me?’

That did it. Anger welled up inside me, pushing my fear to the side.

‘No, I don't understand!’ I snapped, nearly biting off his finger. ‘You two are businessmen, or financiers or whatever you call yourselves - not cold-blooded killers! If he is guilty of this theft, why should I be afraid of him? Why shouldn’t I simply go to the police and tell them what I know!’

‘Which is?’

‘That he’s guilty!’

‘Based on what evidence?’

‘Based on… well…’ For a moment I floundered, but it wasn’t long. ‘Based on Simmons' word, for one. We could make him a witness!’

In answer, Mr Ambrose simply turned and walked away from me. I was about to protest, when he stopped and snatched up a newspaper from his desk. A paper? I frowned. What did he want a paper for?

He came back and held out the paper, opened at a particular page. One section was outlined in blue ink.

‘Read it.’