Another five minutes passed before the footman returned. Without a word, he unlocked the gates, and beckoned them inside. He locked the gates behind them as they walked up the sloping gravelled driveway towards the pillared portico of the house. The flowerbeds all the way along the drive were clustered with white and yellow roses, and the fragrance was almost nauseating. Peter was reminded that he had not eaten anything all day, except for one desultory nibble at his rock cake.

The footman opened the black-painted front doors, and led the friends into a wide, high-ceilinged hallway which had been decorated in a style which Peter could only think of as over-extravagant Byzantine. There were arches everywhere, decorated with gold and peacock-blue mosaics, and a fountain of nude entwined mermaids splashed water into the cool echoing silence.

‘You’ll come through to the afternoon room, sir?’ asked the footman, and ushered them into a sunny yellow-carpeted library at the far side of the hall.

At a wide leather-topped desk, smoking a Turkish cigarette in a long holder, sat a small rotund man with shiny brushed-back hair, and a monocle. He was wearing a yellow silk dressing-gown which matched the colour of the carpet, and yellow silk slippers.

On a chaise-longue at the opposite end of the room, next to a wall of gilded and leather-bound books, lay a very pretty girl who looked no more than sixteen or seventeen years old, with an embroidered silk headband around her blonde, upswept hair, and dressed in a multi-layered negligée of such fine laon and lace that Peter could distinguish the rosy pink of her nipples.

‘You’d better introduce yourselves,’ said the fat man behind the desk.

‘My name’s Peter Ransome,’ said Peter. ‘And this is Mr Samuel Kellogg, my friend. Mr Kellogg is a jeweller.’

‘I see,’ said Garth Steinman. ‘And what are you?’

‘I am an automobile mechanic,’ said Peter.

Garth Steinman jotted a few notes on to the diary that was open in front of him. Then he closed it up, and said, ‘What is an automobile mechanic doing with a large diamond, that’s what I ask myself.’

‘I came by it legitimately, Mr Steinman. It was a bequest from my late mother. My … recently late mother.’

‘My condolences,’ said Garth Steinman. ‘Your mother was a wealthy woman? Should I know her name?’

‘She was not wealthy in any other respect, save this diamond,’ Peter told him, quietly.

Garth Steinman looked up, one eye closed, the other eye staring through his monocle like a freshly opened clam. ‘I see. Well, a diamond’s provenance is not too difficult to check, if you know the right people to ask. My man told me that the stone was exceptional, by all appearances.’