'So, its origin is… a mystery.'

'You could say so, yes.'

'And the person who bought it?'

Garrard smiled. 'What would you like to know?'

'Well, their name and address, if you have the information.'

Unaccountably, Garrard loosed a dry but hearty laugh. His eyes twinkled mischievously. 'Oh dear, oh dear. Here we go again.'

'I'm sorry?'

'Your name would be Umber, I assume.'

'What?' Umber stared at the bookseller in frank astonishment. 'How do you know that?'

'I've been down the Junius road with someone else only last week.'

'Who?'

'A Mr Wisby.'

'Wisby?'

'Yes. He phoned me this morning and said you might call round. This is an entertaining charade, though a baffling one from my point of view. I'm sure you both know what you're about. Still, I've no wish to go on acting as go-between. If I give you his number, I trust that'll be the last I hear of the matter.'

Umber rang Wisby from the first call-box he came to after leaving Quires. The promptness of Wisby's answer suggested he had been waiting for the call.

'Mr Umber.' The susurrous voice was unmistakable, even after more than twenty years.

'Mr Wisby.'

'The very same.'

'I thought you didn't trust phones.'

'Needs must. Besides, communicating with you by letter didn't turn out very satisfactorily, did it?'

'What the hell's going on?'

'Not a hundred per cent certain. But I probably know more than you do. If you want to talk about it, join me in Royal Square in ten minutes.'

It took Umber less than ten minutes to thread his way through the pedestrianized part of the town centre to his destination: a sedate, flagstoned piazza overlooked by the handsome nineteenth-century buildings housing Jersey's parliament and principal court, with a gilded statue of George II tricked out as Caesar presiding at one end.

In the centre of the square, seated on a bench and reading a newspaper, was a lean, round-shouldered man in a brown raincoat and navy-blue trousers. He was smoking a cigarette – and Alan Wisby he had to be.

He looked much as Umber remembered, though greyer, in skin as well as hair, and perhaps even thinner. There was a grizzled moustache too which he might or might not have previously sported, but then he had always possessed a strangely insubstantial quality. He was someone easily forgotten, someone who had refined the art of not being noticed and applied it to his professional purposes. He looked up as Umber approached and nodded an unsmiling greeting. Umber sat down beside him.

'Have you read yesterday's Jersey Evening Post, Mr Umber?' Wisby asked, holding up the newspaper.

'No.'

'Tiny article on page five took my eye. Drug smuggler caught coming off the ferry from Portsmouth Monday night was up before the beak. Name of Sharp. George Sharp.'

'I'm not here to play games, Mr Wisby.'

'Good. Though it's strange you should say that, actually. I'm told someone's been playing games with Monica. My narrowboat, I mean. She was set loose from her mooring on the Kennet and Avon Canal Monday night. Safe in the boatyard at Newbury now, you'll be glad to know. Busy old night, Monday, it seems.'

'I went down to Kintbury at your invitation. You weren't on the boat. Two people were waiting for you, though. Worse luck for me.'

'I spotted them earlier in the day and decided to make myself scarce. I didn't set you up, Mr Umber, if that's what you thought.'

'I didn't, actually.'

'Good.'

'They'd broken into the boat and been through your files.'

'They were welcome to. I'd already removed what they were looking for.'

'And what was that?'

'Well, that's the sixty-four-thousand-dollar question, isn't it? The what, the why and the wherefore.'

'Are you going to answer it?'

'I'm going to try. Where shall we begin?'

'Oliver Hall. What's he been paying you to do?'

'Nothing. I took a look at the Avebury case for Hall back in 1982. That was the last time I had any dealings with the man.'

'I know that's not true. You told Claire Wheatley -'

'I lied.' Wisby smiled fleetingly and flicked away the butt of his cigarette. 'Loose ends have always niggled at me, Mr Umber. When I handed over the day-to-day running of the business to Monica – the other Monica – I revisited a few cases that had left me… dissatisfied. Avebury was always going to be one of them. Your wife's sudden death brought it to the front of the queue. I thought her psychotherapist likelier to cooperate if I led her to believe I was working for Hall. Didn't get much out of her, though.'

'Get much out of anyone?'

'I've made some headway recently. Thanks to Junius.'

'You had a letter too, did you?'

'The same one as Sharp received, I assume. "It is the misfortune of your life that you should never have been acquainted with the truth with respect to the Marlborough murderers." Etcetera, etcetera. Familiar?'

'Word for word.'

'Sharp had you down as prime suspect, I take it.'

'Initially.'

'That's the trouble with policemen. They think in straight lines. Of course, he lacked a crucial piece of information I turned up five years ago. The letter brought it centre stage.'

'What might that be?'

'All in good time, Mr Umber. Let's not rush our fences.' Wisby lit another cigarette. 'I was over here last week double-checking a few points. I hadn't planned to do anything on the strength of my conclusions straight away, but the arrival of the heavy mob canalside forced my hand. That's why I'm back. What about you?'

'George was intending to speak to Jeremy Hall. Someone went to considerable lengths to stop him. So, I reckoned I ought to pay Jeremy a call. But how did you know I was on the island?'

'It stood to reason, with Sharp here as well. I tried a few hotels and struck lucky at the Pomme d'Or. Bringing his van to Jersey wasn't a smart move on Sharp's part. He was asking for trouble. I flew. Like you, I imagine. Have you seen Jeremy yet?'

'Yesterday afternoon.'

'How was he?'

'Not a happy bunny. Threw me out.'

'Understandable. He's under a lot of pressure. I should know, since I'm the one applying it. That's why I steered you towards Quires. So we could get together before you queered the pitch for me.'

'Who bought the vellum-bound Junius? Was it Jeremy?'

'Yes. I had to pay Garrard over the odds for an unreadable history of Jersey before he'd give me a decent description of the customer, but there was no doubt who it fitted. Of course, I could have guessed that anyway. The really important question isn't who bought the book, but where it came from.'

'Garrard said he didn't know.'

'I don't think he does. But it's a vital link in the chain that connects Griffin with Jeremy Hall. We have to know.'

'How do we find out?'

'By forcing Jeremy to tell us. Which brings me to your part in the proceedings. You're the historian, not me. Part of my deal with Jeremy is that he hands over the Junius and in return I don't tell his father he stirred up all this trouble for his family by sending anonymous letters to Sharp and me and God knows who else.'

'Jeremy sent them?'

'I think his purchase of the book proves he did. And the book proves something else. If it's authentic. That's where you come in. I was going to have to back my own judgement but I don't need to with you tagging along. You'll be able to say for certain if it's the copy Griffin promised to show you at Avebury.'

'Well, yes, I can. But -'

'How did it get to Jersey, hey?' Wisby turned to look Umber in the eye. 'And what does it mean? I think I know. I think I have it all worked out.'

'Planning to let me in on the secret?'