'I'll do that, Mr Stafford.' Hoyland seemed relieved. Bucking top management was something he'd rather not do himself.

I put down the telephone and grinned at Charlie. 'See what I mean. How would you handle a thing like that?'

'Franklin Engineering,' he said reflectively. 'Defence contractors, aren't they?'

'They do a bit for the army. Suspension systems for tanks – nothing serious.'

'What are you going to do about it?'

'I'm going to blow hell out of this joker, Isaacson. No money-pusher is going to tell one of my security officers what concerns security and what doesn't.'

Charlie tilted back his chair and regarded me speculatively. 'Why don't you do it personally – face to face? You've been complaining about being tied to your desk, so why don't you pop over to Luton and do some legwork? You can easily get back in time for the board meeting. Get out of the office, Max; it might take that sour look off your face.'

'Is it as bad as that?' But the idea was attractive, all the same. 'All right, Charlie; to hell with the desk!' I rang Joyce. 'Get on to Hoyland at Franklin Engineering – tell him I'm on my way to Luton and to hold himself available.' I cut off her wail of protest. 'Yes, I know the state of the in-tray it'll get done tomorrow.'

As I put down the telephone, Charlie said, 'I don't suppose it is really important.'

'I shouldn't think so. The man's either gone on a toot or been knocked down by a car or something like that. No, Charlie; this is a day's holiday, expenses paid by the firm.'

I should have remembered Hoyland's name because I remembered his competent, square face when I saw it. He was a reliable type and an ex-copper like so many of our security officers. He was surprised to see me; it wasn't often that the top brass of Stafford Security appeared in the front line, more's the pity.

His surprise was mingled with nervousness as he tried to assess why I had come personally. 'Nothing to worry about,' I assured him. 'Only too glad to get away from the desk. Tell me about Billson.'

Hoyland rubbed his chin. 'I don't know much about him. You know I've only been here three months; I was transferred here when Laird retired.'

I didn't know – there was too damned much about my own firm I didn't know. It had grown too big and depersonalized. 'Yes,' I said.

'I took over Laird's files and checked his gradings. Billson came well into the green scale – as safe as houses. He was at the bottom of my priorities.'

'But you've rechecked since he disappeared?'

Hoyland nodded. 'Forty-four years old, worked here fifteen years. As much personality as a castrated rabbit. Lodges with a Mrs Harrison in the town. She's a widow.'

'Anything between him and Mrs Harrison?'

Hoyland grinned. 'She's seventy.'

That didn't mean much; Ninon de L'Enclos was a whore at eighty. 'What about girl-friends?'

'Not Billson – the girls didn't go for him from what I've heard.'

'All right – boy-friends?'

'Not that, either. I don't think he was the type.'

'He doesn't seem much of anything,' I said caustically.

'And that's a fact,' said Hoyland. 'He's so insignificant he hardly exists. You'd walk past him and not know he was there.'

'The original invisible man,' I commented. 'All the qualifications for a sleeper.'

'Isn't fifteen years too long?' queried Hoyland. 'Besides,' he left everything in order.'

'As far as we know, that's all. Do the Special Branch boys know about this?'

'They've been poking around and come to the same conclusion as me.'

'Yes,' I said. 'Billson is probably in some hospital, having lost his means of identification. But there is a mystery; why was he overpaid and why is management being coy about it?'

Hoyland nodded. 'I talked to Stewart about it first – he's Billson's immediate boss – and he pushed me on to Isaacson. I got nowhere with him.'

I'll see what I can do,' I said, and went to find Stewart, who proved to be a sandy Scotsman, one of the new breed of bookkeepers. No dusty ledgers for him; figures were something which danced electronically in the guts of a computer.

No, he had no idea where Billson might have gone. In fact, he knew nothing about Billson, full stop.

'Isn't that a little odd for a department head? Surely you know something about your subordinates?'

'He's a very strange man,' said Stewart. 'Reserved most of the time but capable of the most frantic outbursts occasionally. Sometimes he can be very difficult.'

'In what way?'

Stewart shrugged. 'He goes on about injustice; about people not being given the proper credit for achievement. He's very bitter about it.'

'Meaning himself?'

'No; it was always about others being repressed or cheated.'

'Any political implications?'

'Not at all,' said Stewart positively. 'Politics mean nothing to him.'

'Did he do his work well?'

Stewart offered me a wary look and said over-carefully, 'He did the work we asked of him to our satisfaction.'

'Would you say he was an achiever himself?' I smiled. 'Was he in line for promotion, or anything like that?'

'Nothing like that.' Stewart seemed aware that he had spoken too quickly and emphatically. 'He's not a dynamic man.'

'I said, 'When did you join the firm, Mr Stewart?'

'Four years ago. I was brought down from Glasgow when the office was computerized.'

'At that time did you make any attempt to have Billson fired or transferred to another department?'

Stewart jerked. 'I… er… I did something like that, yes. It was decided to keep him on.'

'By Mr Isaacson, I take it.'

'Yes. You'll have to ask him about that,' he said with an air of relief.

So I did. Isaacson was a more rarefied breed of accountant than Stewart. Stewart knew how to make figures jump through hoops; Isaacson selected the hoops they jumped through. He was an expert on company law, especially that affecting taxation.

'Billson!' he said, and smiled. 'There's a word in Yiddish which describes a man like Billson. He's a nebbish.'

'What's that?'

'A person of less than no account. Let me put it this way; if a man walks out of a room and it feels as though someone has just come in, then he's a nebbish.'

I leaned back in my chair and stared at Isaacson. 'So here we have a nebbish who draws?8000 for a job worth?2000, if that. How do you account for it?'

'I don't have to,' he said easily. 'You can take that up with our managing director, Mr Grayson.'

'And where will I find Mr Grayson?'

'I regret that will be difficult,' said Isaacson in a most UN-REGRETFUL manner. 'He's in Switzerland for the skiing.'

He looked so damned smug that I wanted to hit him, but I kept my temper and said deliberately, 'Mr Isaacson, my firm is solely responsible for security at Franklin Engineering. A man has disappeared and I find this lack of co-operation very strange. Don't you find it odd yourself?'

He spread his hands. 'I repeat, Mr Stafford, that any questions concerning Mr Billson can be answered only by my managing director.'

'Who is sliding down hills on a couple of planks.' I held Isaacson's eye. 'Stewart wanted to fire Billson but you vetoed it. Why?'

'I didn't Mr Grayson did. He said Billson must stay.'

'Surely you asked his reasons.'

'Of course.' Isaacson shook his head. 'He gave none.' He paused. 'I know nothing of Billson, Mr Stafford, other than that he was… protected, shall we say.'

I thought about that. Why should Grayson be Billson's fairy godfather? 'Did you know that Billson was "protected" when Stewart wanted to fire him?'

'Oh yes.' Isaacson smiled a little sadly. 'I wanted to fire him myself ten years ago. When Stewart brought up the suggestion I thought I'd test it again with Mr Grayson.' He shrugged. 'But the situation was still the same.'