Sir Walter had taken each note from its envelope, but had paper-clipped the envelopes to the backs of their respective notes. So Rebus was able to ascertain that the notes had been posted between three weeks and one week ago, and all bore a central London postmark. He read the three notes slowly to himself, then reread them. The first came quickly to its point.

I ENCLOSE A LETTER. THERE ARE PLENTY MORE WHERE IT CAME FROM. YOU WILL HEAR FROM ME AGAIN.

The second fleshed out the blackmail.

I HAVE ELEVEN MORE LETTERS. IF YOU’D LIKE THEM BACK, THEY WILL COST £2,000. GET THE MONEY.

The third, posted a week ago, finalised things.

PUT THE MONEY IN A CARRIER BAG. GO TO THE CAFE ROYAL AT 9 P.M. FRIDAY. STAND AT THE BAR AND HAVE A DRINK. LEAVE THE BAG THERE AND GO MAKE A PHONE CALL. SPEND TWO MINUTES AWAY FROM THE BAR. WHEN YOU COME BACK, THE LETTERS WILL BE THERE.

Rebus looked up at Lady Scott. ‘Did he pay?’

‘I’ve really no idea.’

‘But you could check?’

‘If you like, yes.’

Rebus nodded. ‘I’d like to be sure.’ The first note said that a letter was enclosed, obviously a letter concerning Sir Walter – but what kind of letter? Of the letter itself there was no sign. Twelve apparently incriminating or embarrassing letters for £2,000. A small price to pay for someone of Sir Walter’s position in society. What’s more, it seemed to Rebus a small price to ask. And if the exchange had taken place as arranged, what was the point of the last note, the one found in Sir Walter’s binocular case? Yes, that was a point.

‘Did you see the mail this morning, Lady Scott?’

‘I was first to the door, yes.’

‘And was there an envelope like these others?’

‘I’m sure there wasn’t.’

Rebus nodded. ‘Yes, if there had been, I think Sir Walter would have kept it, judging by these.’ He shook the notes – all with envelopes attached.

‘Meaning, John?’ Superintendent Watson sounded puzzled. To Rebus’s ears, it was his natural voice.

‘Meaning,’ he explained, ‘that the last note, the one we found on Sir Walter, was as it arrived at the house. No envelope. It must have been pushed through the letterbox. I’d say sometime yesterday or this morning. The blackmail started in London, but the blackmailer came up here for the payoff. And he or she is still here – or was until midday. Now, I’m not so certain. If Sir Walter paid the money’ – he nodded towards Lady Scott – ‘and I would like you to check on that, please, today if possible. If, as I say, Sir Walter paid, if he got the letters back, then what was this morning’s little game all about?’

Watson nodded, arms folded, looking down into his lap as though seeking answers. Rebus doubted they’d be found so close to home. He rose to his feet.

‘We could do with finding those letters, too. Perhaps, Lady Scott, you might have another look in your husband’s… office.’

She nodded slowly. ‘I should tell you, Inspector, that I’m not sure I want to find them.’

‘I can understand that. But it would help us track down the blackmailer.’

Her voice was as low as the light in the room. ‘Yes, of course.’

‘And in the meantime, John?’ Watson tried to sound like a man in charge of something. But there was a pleading edge to his voice.

‘Meantime,’ said Rebus, ‘I’ll be at the Castellain Hotel. The number will be in the book. You can always have me paged.’

Watson gave Rebus one of his dark looks, the kind that said: I don’t know what you’re up to, but I can’t let anyone else know that I don’t know. Then he nodded and almost smiled.

‘Of course,’ he said. ‘Yes, off you go. I may stay on a little longer…’ He looked to Lady Scott for her assent. But she was busy with the handkerchief again, twisting and twisting and twisting…

The Castellain Hotel, a minute’s walk from Princes Street, was a chaos of tourists. The large pot-planted lobby looked as though it was on someone’s tour itinerary, with one large organised party about to leave, milling about as their luggage was taken out to the waiting bus by hard-pressed porters. At the same time, another party was arriving, the holiday company’s representative conspicuous by being the only person who looked like he knew what was going on.

Seeing that a group was about to leave, Rebus panicked. But their lapel badges assured him that they were part of the Seascape Tours package. He walked up to the reception desk and waited while a harassed young woman in a tartan two-piece tried to take two telephone calls at the same time. She showed no little skill in the operation, and all the time she was talking her eyes were on the scrum of guests in front of her. Finally, she found a moment and a welcoming smile for him. Funny how at this time of year there were so many smiles to be found in Edinburgh…

‘Yes, sir?’

‘Detective Inspector Rebus,’ he announced. ‘I’d like a word with the Grebe Tours rep if she’s around.’

‘She’s a he,’ the receptionist explained. ‘I think he might be in his room, hold on and I’ll check.’ She had picked up the telephone. ‘Nothing wrong, is there?’

‘No, nothing, just want a word, that’s all.’

Her call was answered quickly. ‘Hello, Tony? There’s a gentleman in reception to see you.’ Pause. ‘Fine, I’ll tell him. ’Bye.’ She put down the receiver. ‘He’ll be down in a minute.’

Rebus nodded his thanks and, as she answered another telephone call, moved back into the reception hall, dodging the bags and the worried owners of the bags. There was something thrilling about holidaymakers. They were like children at a party. But at the same time there was something depressing, too, about the herd mentality. Rebus had never been on a package holiday in his life. He mistrusted the production-line cheerfulness of the reps and the guides. A walk along a deserted beach: now that was a holiday. Finding a pleasant out-of-the-way pub… playing pinball so ruthlessly that the machine ‘tilted’… wasn’t he due for a holiday himself?

Not that he would take one: the loneliness could be a cage as well as a release. But he would never, he hoped, be as caged as these people around him. He looked for a Grebe Tours badge on any passing lapel or chest, but saw none. The Edinburgh Castle gatekeepers had been eagle-eyed all right, or one of them had. He’d recalled not only that a Grebe Tours bus had pulled in to the car park at around half past eleven that morning, but also that the rep had mentioned where the tour party was staying – the Castellain Hotel.

A small, balding man came out of the lift and fairly trotted to the reception desk, then, when the receptionist pointed towards Rebus, trotted over towards him, too. Did these reps take pills? potions? laughing gas? How the hell did they manage to keep it up?

‘Tony Bell at your service,’ the small man said. They shook hands. Rebus noticed that Tony Bell was growing old. He had a swelling paunch and was a little breathless after his jog. He ran a hand over his babylike head and kept grinning.

‘Detective Inspector Rebus.’ The grin subsided. In fact, most of Tony Bell’s face seemed to subside.

‘Oh Jesus,’ he said, ‘what is it? A mugger, pickpocket, what? Is somebody hurt? Which hospital?’

Rebus raised a hand. ‘No need to panic,’ he reassured him. ‘Your charges are all quite safe.’

‘Thank Christ for that.’ The grin returned. Bell nodded towards a door, above which was printed the legend Dining-Room and Bar. ‘Fancy a drink?’

‘Anything to get out of this war zone,’ Rebus said.

‘You should see the bar after dinner,’ said Tony Bell, leading the way, ‘now that’s a war zone…’

As Bell explained, the Grebe Tours party had a free afternoon. He checked his watch and told Rebus that they would probably start returning to the hotel fairly soon. There was a meeting arranged for before dinner, when the next day’s itinerary would be discussed. Rebus told the rep what he wanted, and Bell himself suggested he stay put for the meeting. Yes, Rebus agreed, that seemed sensible, and meantime would Tony like another drink?