Nick produced his warrant card and the other’s face dropped. ‘Now what, for Christ’s sake?’

He opened the door and Nick followed him out into the corridor, closing the door behind him, effectively cutting off most of the din.

‘No trouble,’ he said. ‘I’m just trying to trace a bloke who lives upstairs – Chuck Lazer. He wouldn’t be inside by any chance?’

The young man grinned, took a cigarette from behind his ear and stuck it in the corner of his mouth. ‘Chuck? I should say not! Moves in his own narrow circle, God help him.’

‘Is he still on junk?’ Nick said.

‘As far as I know, but he’s a registered user now.’ The young man frowned suddenly. ‘Look, what is all this?’

‘Nothing to get worked up about, I’m not trying to hang anything on him. I want his help with a routine enquiry, that’s all.’

‘That’s what you lot always say.’

Nick shrugged. ‘Suit yourself.’

He turned towards the door and the young man said quickly: ‘Oh, what the hell. He overslept, missed the evening surgery. Someone came looking for him about half an hour ago.’

‘What kind of someone?’

‘Big man, dirty raincoat, Irish looking.’ The young man grinned suddenly. ‘That cap’s the coolest thing I’ve seen in years. Where can I get one?’

‘Any good men’s shop in Hamburg. Did they leave together?’

The young man shook his head. ‘Lazer went out about ten minutes ago. I was having five minutes with one of the birds up at the end of the passage when he came down.’

‘Was he in a hurry?’

‘They always are when they need a fix. I’d say he was on his way round to see his quack about a prescription.’

‘And who would that be?’

‘Dr Das, just round the corner in Baron’s Square. He’s about the only one in town who’ll take junkies on his list. Say, are you really a copper?’

‘As ever was.’

‘Crazy!’ the young man said, frank admiration in his eyes. ‘If I join will they guarantee me a uniform like that?’

‘I’ll mention it to the Chief Constable in the morning. We’ll be in touch.’

‘You do that, man.’

He opened the door and returned to his party as Nick went down the steps into the rain. There was a touch of fog in the air, heavy and acrid, catching at the back of the throat, and he climbed behind the wheel of the Mini-Cooper and drove around the corner to Baron’s Square.

Dr Das lived at number twenty and a brass plate on the door disclosed the surprising fact, considering the district and circumstances, that he was not only an MD but also a Fellow of the Royal College of Physicians.