He paid for his coffee at the desk, shrugged on his coat, and stepped out into the rainy daylight. At the next corner, he flagged a cab down and asked to be taken to Sacramento Street. He sat back on the wet leather seats, smoking and impatiently watching the raindrops trickle and jerk their way down the window. When they reached the firehouse on Sacramento and Kearny, he rapped on the hood for the driver to stop, and he climbed out. The rain was easing off now, and there was a wash of glittering yellow sunlight on the sidewalks. He was pleased about that, because to complete his alibi he was going to have to walk three blocks to Bush Street, right down to the next firehouse, and hope that he didn’t run into anybody who might recognise him.

He reached Maria-Mamuska’s house with his shoes spattered in mud. The Chinese girl let him in, took his coat and his umbrella, and gave him a pair of oriental silk slippers in vivid green. Andy Hunt, in a loud brown herring-bone suit, was waiting impatiently for him in the front parlour.

‘Well?’ asked Collis. ‘What’s happening?’

‘This had better not backfire,’ said Andy. ‘By God, I tell you, Collis, if this backfires—’

‘It’s not going to backfire,’ Collis told him sharply. ‘Now, what’s happening? Did she get here all right?’

‘Sure. Dan had her blindfolded and everything. We took her upstairs to Maria’s back bedroom and she’s there now.’

‘Did she take the opium?’

Andy nodded. ‘She struggled at first, and wouldn’t drink it. But Maria had the answer. She told her it wasn’t poison, and that if she wouldn’t swallow it, she’d have all her hair cut off. Well, that did the trick. She drank it right down without any more fuss.’

Collis took out his watch. ‘How long ago was that?’

‘Not long. Ten minutes or so.’

‘Is Figgis here?’

‘Oh, yes. He’s been here since two.’

Collis thought for a moment, and then said, ‘All right. Let’s go up and take a look.’

They climbed the narrow, soft-carpeted staircase to the landing. There Andy opened the first door on the right-hand side and led Collis into a small front room, wallpapered in dark purple, with a purple velvet daybed and two plushy purple armchairs. Andy went over to the wall and beckoned Collis to come closer. Then he lifted a small wooden flap on the wall and peered through a spyhole which gave out on to the larger back bedroom where Sarah was being held.

‘Let me see,’ said Collis. Andy put his finger to his lips.

Through the spyhole, Collis could see only part of the room. He could make out the foot of Mr Figgis’s tripod, and a part of Maria-Mamuska’s gown, but for the moment he couldn’t see Sarah at all. Perhaps she was already asleep, and Maria-Mamuska’s maid was undressing her. He turned back to Andy and whispered, ‘I don’t see her. It looks as though the opium’s worked.’