But Andy was just about to take another peek when a clear, distinctive voice said, ‘I really don’t know why you’re keeping me here. My father will make sure that every one of you is hanged.’

Andy looked at Collis and made a face. ‘Doesn’t sound as though she’s very sleepy, does it?’

Collis put his eye to the spyhole again. He saw Sarah this time, as she stalked haughtily across the room with her arms folded. She was still wearing her grey overcoat and her bonnet. Then he saw Dan McReady, flushed and sweating, his false moustache hanging loose from one side of his cheek. Then Sarah appeared again, as awake and as intractable as before.

‘You sure Mr Kwang didn’t sell you a pup?’ asked Andy.

‘I don’t know,’ said Collis. ‘What do I know about opium?’

‘Well, if she doesn’t zizz off soon, we’re sunk,’ said Andy. ‘She may take a drink if we threaten to cut her hair off, but you can bet your boot buttons she ain’t going to take off her clothes.’

‘Damn,’ said Collis, to nobody in particular, as he saw Sarah walk across the room again.

A door opened and closed, and then Dan McReady and Maria-Mamuska appeared in the back bedroom, perspiring and dispirited. Maria had disguised herself with a black lace-edged mask, but when she saw Collis she pulled it off and threw it aside.

‘That lady may be everything you say she is,’ Maria-Mamuska told Collis. ‘But one thing she isn’t, and that’s sleepy.’

‘She’s not even yawning,’ said Dan.

Collis sat down on the daybed and looked at them without saying a word. If they didn’t get their calotypes, Sarah’s abduction would be nothing more than a ridiculous charade. Apart from the sheer absurdity of returning Sarah to the bosom of her family completely unharmed and untouched, at the cost of two cabs, one Chilean fish-crate wagon driver, two cups of coffee, and a lemon pastry he hadn’t eaten, there was the painful prospect of having to go back to Hannah and admit that his wonderful secret plan, the plan which had led to so many arguments, had dismally failed.

‘It’s that Chinese bastard, Kwang,’ Andy said. ‘He probably gave you a bottle of rice wine, or pig’s piss, or whatever it is those Chinks use to cook with.’

Collis shrugged. ‘He said it was opium tincture, and strong, too. How much did you give her?’

‘Four spoonfuls, just as you said.’

‘Well, I don’t understand it,’ said Collis. ‘He specifically said that if she had anything more than a few drops, she’d fall flat on her back. He warned me not to give her too much, in case it killed her.’

‘Aah, you know what these Chinese are like,’ said Andy. ‘All noodles and shrimps and hocus-pocus.’

‘What are we going to do?’ asked Maria-Mamuska softly. ‘If she doesn’t sleep, then we can’t take the pictures.’

‘I’m thinking,’ said Collis. ‘There has to be a way out of this somehow.’