Laurence Melford raised a hand. ‘It’s all right, Carlo. I can deal with this. Mr Edmonds and I go through this kind of performance with tiresome regularity.’

‘I didn’t want to bother you for long,’ Collis said. ‘Just long enough to say “Calotypes”.’

Laurence Melford’s cheeks tightened, and his eyes suddenly looked very dark. Andrew Crawford noticed the change in him and frowned uncertainly. ‘Larry?’ he asked. ‘Do you want me to leave? I don’t mind if it’s really important.’

Laurence Melford hesitated, and then nodded. ‘Just for a minute or two, please, Andrew. Carlo — would you take Mr Crawford’s lunch to that table over there for him, please? And would you bring a drink for Mr Edmonds?’

Andrew Crawford stood up, and Collis sat down in his place. Before the waiter arrived to take the plate away, Collis forked up one of Andrew Crawford’s slices of venison, and he chewed it placidly while he waited for his drink. Laurence Melford watched him with the patronising coldness of a god on Mount Olympus.

‘Well?’ he asked, after Carlo had set down a stone fence and left them alone.

‘Well,’ said Collis, running his fingertip around the rim of his glass, ‘I hear you’re having some embarrassing trouble. I also hear that the trouble isn’t completely unconnected with photographic reproductions of a member of your family.’

‘How did you hear that?’ he said harshly.

‘Mr Melford, I was a tenderfoot in San Francisco when you first met me, but these days I’m a little more au fait.’

‘I suppose you set up this dirty little business yourself?’

‘Mr Melford, I’m a respectable hardware dealer from a respectable city. I’m also a partner in the Sierra Pacific Railroad Company. You don’t seriously think that I’d get myself involved in a nasty affair like this, do you?’

‘Yes, if you want my candid opinion,’ said Laurence Melford. ‘But I don’t suppose I’ll ever be able to prove it.’

Collis swilled his drink around his mouth before swallowing it. ‘I happen to be friends with the leaders of several Chinese tongs, Mr Melford. If you hadn’t been so racially prejudiced, you would have had the good sense to cultivate a friendship with them yourself. They are the wisest and the best-informed men in the whole of this city.’

‘They’re a collection of crooks,’ remarked Laurence Melford.

‘Yes,’ agreed Collis. ‘But it takes a crook to know what crooks are up to; and they tell me on excellent authority that Sarah was temporarily abducted last week for the purposes of a very novel and ingenious crime.’

Laurence Melford toyed with his fork. His suppressed anger made the glasses and plates tremble.