We didn’t use the main lift but a dingy service lift at the rear of the building, emerging into a garage. Negrini nodded towards a Cadillac. ‘That’s mine.’ We went over and he opened the boot. ‘Jump in.’

‘For God’s sake!’

‘This is the way Hanna wants it,’ said Negrini sharply. ‘He doesn’t want you out in the open.’

‘I’m sorry,’ I said. ‘I left my cloak and dagger upstairs.’ Negrini made an impatient noise so I obediently got into the boot and he slammed down the lid. There’s one thing about big American cars: they have plenty of luggage space, so I wasn’t cramped at all. I was glad Negrini didn’t drive a Volkswagen.

I lay there for more than twenty minutes and amused myself by trying to estimate just where the car was at every stage of the journey. We crossed to the mainland on the ferry and then went along the waterfront and past the market. After that I got lost. Eventually, after an unexpected swooping passage that reminded my stomach of a roller-coaster, the engine stopped and presently Negrini opened the boot.

I climbed out stiffly and stretched. We were in an underground garage in what was presumably police headquarters. There was a line of Black Marias and, in a far corner, a couple of armoured cars equipped with water cannon. A man in plain clothes was standing by. He said quietly, ‘This way, Mr Kemp,’ and led us to a lift.

As we went up, I said to Negrini, ‘I have a nasty feeling I’m on the verge of being arrested for something.’

He grinned. ‘Broken any laws lately?’

‘None that I can think of, but I’m not at all sure that’s necessary here.’

The lift stopped and the door opened. Standing in the corridor was a uniformed policeman, who nodded briefly to our escort. ‘Move quickly, Mr Kemp,’ said the man at my side, and emphasised his words with a push.

We walked along the corridor and around a corner. I noticed what seemed to be a relay team of police stationed at strategic points and we were hastened along by a series of nods and beckoning arms. At last we went past a door, through an outer office and into Hanna’s sanctum. The lights were on and the venetian blinds were drawn.

Hanna looked up, waved away our escort, and said, ‘I suggest you leave and have a cup of coffee, Mr Negrini. Come back in half an hour.’

‘Goddamn it!’ said Negrini. ‘What am I? A chauffeur service for the cops?’

‘Your services are appreciated, of course,’ said Hanna. ‘But there are things which Mr Kemp and I must discuss in private.’

‘I get it,’ said Negrini. ‘What I don’t know won’t hurt you. Okay, Bill, I’ll be back in half an hour.’