I pulled up beside a telephone box and put through a reversed charge call to the Suffolk police.

'Is Detective Chief Superintendent Irestone there?' I said. Hopeless question, but had to be asked.

'Your name, sir?'

'Jonathan Derry.'

'One moment.'

I waited through the usual mutterings and clicks, and then a voice that was still not Irestone's said, 'Mr Derry, Chief Superintendent Irestone left instructions that if you telephoned again, your message was to be taken down in full and passed on to him directly. Chief Superintendent Irestone asked me to say that owing to… er… a hitch in communications he was not aware that you had tried to reach him so often, not until this afternoon. I am Detective Inspector Robson. I came to your house with the Chief Superintendent, if you remember.'

'Yes,' I said. A man nearing forty, fair-headed, reddish skin.

'If you tell me why you rang, sir?'

'You'll take notes?'

'Yes, sir. And a recording.'

'Right. Well – the man who came to my house with a pistol is called Angelo Gilbert. His father is Harry Gilbert, who runs bingo halls all over Essex and north-east London. The man who came with Angelo is his cousin Eddy – don't know his last name. He does what Angelo tells him.'

I paused and Inspector Robson said, 'Is that the lot, sir?'

'No, it isn't. At this moment all three of them are travelling from Norwich in Angelo's car.' I told him the make, the colour, the number, and that it had a bashed-in nearside rear wing. 'They are probably going to Harry Gilbert's house in Welwyn Garden City. I think Angelo also lives there, but perhaps not Eddy.' I gave him the address. 'They should arrive there in about an hour and a quarter to an hour and a half. In the car there is a Walther. 22 pistol with a silencer. There may or may not be bullets in it. It may or may not be the pistol which Angelo waved at me, but it looks identical. It might be the pistol which killed Christopher Norwood.'

'That's very useful, sir,' Robson said,

'There's one more thing…'

'Yes?'

'I don't think Harry Gilbert knows anything at all about Chris Norwood's death. I mean, I don't think he even knows he's dead. If you go to arrest Angelo, Harry Gilbert won't know why.'

'Thank you, sir.'

That's all,' I said.

'Er,' he said,'the Chief Superintendent will be in touch with you.'

'All right, but-' I hesitated.

'Yes, sir?'

'I'd be glad to know…'

'Just a minute, sir,' he interrupted, and kept me hanging on through some lengthy unintelligible background talk. 'Sorry, sir, you were saying?'

'You remember I sent Angelo some computer tapes with games on?'

'Yes, I do. We went to Cambridge main post office and alerted the man whose job it was to hand out letters-to-be-called-for, but unfortunately he went for his tea-break without mentioning it to anyone, and during that short period your package was collected. A girl clerk handed it over. We didn't find out until it was too late, It was… infuriating.'

'Mm,' I said. 'Well, Angelo came back with more threats, demanding the real tapes, and I've just given them to him. Only…'

'Only what, sir?'

'Only they won't be able to run them on their computer. I think when they get home they might try those tapes straight away, and when they find they don't work they might… well they might set out to look for me. I mean-'

'I know exactly what you mean,' he said dryly.

'So, er, I'd be glad to know if you plan to do anything about Angelo this evening. And if you think there's enough to hold him on.'

'Instructions have already gone off,' he said. 'He'll be picked up tonight as soon as he reaches the house in Welwyn. We have some fingerprints to match… and some girls who saw two men arrive at Norwood 's. So don't worry, once we've got him, we won't let him go.'

'Could I ring up to find out?'

'Yes.' He gave me a new number. 'Call there. I'll leave a message. You'll get it straight away.'

'Thank you,' I said gratefully,'very much.'

'Mr Derry?'

'Yes?'

'What's wrong with the tapes this time?'

'Oh, I stuck magnets into the cases.'

He laughed. 'I'll see you later, perhaps,' he said. 'And thanks. Thanks a lot.'

I put the receiver down smiling, thinking of the three powerful Magnadur magnets distorting the programs on the tapes. The permanent magnets which were black and flat; two inches long, three-quarters of an inch wide, three-sixteeenths of an inch thick. I'd stuck one into the inside of each case, flat on the bottom, black as the plastic, looking like part of the case itself. I'd taken the tapes and the cases separately to Harry Gilbert's- the tapes in the one pocket, the cases in another- and only after he'd played them had I married them all together. Sandwiching electro-magnetic recording tapes between such magnets was like wiping a blackboard roughly with a wet sponge: there would be traces of what had been recorded there, but not enough to make sense.

It might take Angelo all the way home to see what I'd done, because the magnets did look as if they belonged there.

Or it might not.

I drove wearily in the direction of home. I seemed to have been driving for ever. It had been a very long day. Extraordinary to think it was only that morning that I'd set out from Ted Pitts's.

Both of the girls went to sleep as the miles unrolled, the deep sleep of release and exhaustion. I wondered briefly what would become of us in the future, but mostly I just thought about driving and keeping my own eyelids apart.

We stayed in a motel on the outskirts of London and slept as if dead. The alarm call I'd asked for dragged me from limbo at seven in the morning and, yawning like a great white shark, I got through to the number Inspector Robson had given me.

'Jonathan Derry,' I said. 'Am I too early?'

It was a girl's voice which answered, fresh and unofficial. 'No, it's not too early,' she said. 'John Robson asked me to tell you that Angelo Gilbert and his cousin Eddy are in custody.'

'Thank you very much.'

'Any time.'

I put the receiver down with a steadily lightening heart and shook Sarah awake in the next bed.

'Sorry,' I said, 'but I've got to be in school by nine o'clock.'

There was a period when Sarah went back to work and Donna drooped around our house trying to come to terms with the devastation of her life. Sarah's manner to her grew gradually less over-protective and more normal, and when Donna found she was no longer indulged and pampered every waking minute she developed a pout in place of the invalid smile, and went home. Home to sell her house, to collect Peter's insurance money, and to persuade her Probation Officer to take Sarah's psychological place.

On the surface, things between myself and Sarah continued much as before: the politeness, the lack of emotional contact, the daily meetings of strangers. She seldom met my eye and seemed only to speak when it was essential, but I slowly realised that the deeply embittered set of her mouth, which had been so noticeable before the day we set off to Norwich, had more or less gone. She looked softer and more as she had once been and although it didn't seem to have altered her manner towards me it was less depressing to look at.

In my inner self a lot had changed. I seemed to have stepped out of a cage. I did everything with more confidence and more satisfaction. I shot better. I taught with zest. I even found the wretched exercise books less of a drag. I felt that one day soon I would stretch the spreading wings, and fly.

One night as we lay in the dark, each in our frostily separate cocoon, I said to Sarah, 'Are you awake?'

'Yes.'

'You know that at the end of term I'm going to Canada with the rifle team?'