'She's got no need to be frightened of them, for God's sake, they're only people. It's just the air trip getting to her stomach, that's all.'

'This is all we needed.'

'It's what we've got. We'll muddle through somehow, we're British.'

The stink of the smoke in here was enough to make anyone sick, it wasn't the air trip, but you're wrong, my little love, you're wrong, you know, there is every need to be frightened of these people, there is every need. They are the people with the tanks.

Movement suddenly at the desk as the officer got to his feet and another one came up and the plainclothes supervisor nodded and turned away and the man from the Bureau swung his head and looked at me with his mouth relaxed and I saw Dr Xingyu Baibing leave the desk and pick up his bag and walk slowly away, folding his papers and putting them into the pocket of his sheepskin coat. I went forward and passed through the checkpoint and then customs and joined our charter group.

'How is your toothache?'

'Much better.'

But he was reading a newspaper.

CAAC Charter Flight No. 4401 to Gonggar will depart from Gate 6 at 12:15. All passengers must report to Gate 6 for embarkation.

They were already lined up, windbreakers and sheepskin jackets and woollen hats and skiing gloves or red hands rubbing together, heavy boots, combat boots, a whole line of boots with the people tethered by them to the littered concrete, swaying in the stream of cold filthy air from the ventilators, all of them except Xingyu Baibing.

He was reading a newspaper, standing near the poster on the wall, Mitsubishi, holding the paper quite still and concentrating on a certain page, a certain column, and as I walked over to him I knew I'd blown Bamboo.

I shouldn't have let him buy a paper.

They hadn't set a trap for him here in Chengdu, specifically. They'd set a trap for him everywhere, wherever he might go, once he'd got out of Hong Kong. They'd been prepared even for the impossible, that somehow, despite their agents there, he'd get clear of Hong Kong, and they'd set a supertrap that couldn't fail.

He was in it now and it had sprung.

'We're boarding,' I said, as if nothing had changed, as if by one chance in a thousand I was wrong.

He looked at me, his eyes smouldering, the newspaper trembling between his hands.

Passengers for Flight No. 4401 for Gonggar are now boarding. All passengers for Gonggar must report immediately to Gate 6 for departure.

Xingyu pushed the newspaper towards me.

'Dead.'

Top of page two.

WIFE OF DISSIDENT IN PRISON. Dr Xingyu Chen, wife of the exiled scientist Xingyu Baibing, who left the People's Republic yesterday in disgrace, was arrested late last night in their apartment in Beijing and taken to Bambu Qiao Prison, where she is now undergoing intensive interrogation, in the hope that she can be persuaded to inform the authorities on the whereabouts of certain friends and colleagues also wanted for questioning, and to offer information particularly on her husband's subversive activities at the university.

Though nothing official has been announced, a source requesting anonymity has declared that if the exiled dissident Xingyu Baibing were to return voluntarily to Beijing for interrogation, his wife would in all likelihood be released immediately.

I folded the paper.

'Hey, come on! You're with our lot, aren't you?'

Xingyu stood facing me.

'I must go to Beijing.'

'No,' I said, 'you can't do that.'

'You cannot stop me.'

She came floating toward me, big eyes in a small pinched face, her body swathed in the folds of a hooded fur jacket too big for her, the hide torn and patched and stained, floating toward me looking rather like an Eskimo child, though she wasn't a child, more like a grown-up china doll.

'They have asked me to assist them,' she said.

I tried to relax, and she stopped floating. On our way from Gonggar to the city the tour guide had told us that at eleven thousand feet we might hallucinate sometimes; there was oxygen, he said, at most of the hotels.

'Assist them?'

I didn't know why it was anything to do with me that they'd asked her to assist them; the people in uniform behind the long cluttered counter, Chinese Public Security officers, one of them watching me steadily, would have worried me if it weren't for the fact that he'd never seen me before, hadn't been outside the airport in Hong Kong when we'd done the Xingyu thing. On the other hand I wasn't totally at ease: they'd picked me up in a military jeep and brought me here for questioning and my passport and visa and Alien Travel Permit were spread all over the counter and the PSB officer would certainly recognize me again if we crossed paths.

'With your case,' she said.

I hadn't got a case. I'd left it in my cell at the monastery with Xingyu looking after it.

'I see,' I said.

She meant my case, of course, criminal charges, so forth. I suppose if the Bureau knew I'd got arrested within an hour of entering Lhasa on a strictly zero-zero clandestine operation they'd call me in straight away, wouldn't blame them. But that wasn't all I'd done since we'd flown out of Chengdu, it was not all, my good friend, that I had done. But I don't want to think about that now, I want to listen to this little china doll and find out if I can rescue anything from the wreckage.

Xingyu is safe.

Yes, concentrate on that. He is safe and among friends at the monastery and you can say, if you want to be charitable, that I've completed the mission, the objective of which was to get Dr Xingyu Baibing out of Hong Kong. But we remember, don't we, that Bamboo has a new objective now: I have to get him back into Beijing when the time is right, and I'm not sure how I can do that if these people throw me into jail.

I think she was waiting for me to say something.

'What exactly is my case?"

'You were out of bounds.'

'Ah. I didn't know.'

In fact when the military jeep had pulled up and the soldier had shouted something to me above the noise of the engine I'd thought he was offering me a lift.

I told her this.

The throttle had got stuck, I suppose, with the engine roaring like that; or he was having to keep it running somehow with the windchill at minus forty degrees. She was telling them what I'd said, in very fast Mandarin, her tiny porcelain teeth flashing their way through the syllables. Mandarin has got something like four hundred syllables and they've all got several tones and if you don't get them exactly right you might as well speak Dutch, it's a real bitch.

'They say there are signs posted.'

'I don't read Chinese.'

'There are signs in English: Military road. Out of bounds.'

'I didn't see anything in the kind of English anyone would recognize.'

'I must not tell them that.'

'I know.'

I'd said it to find out which side she was on, though it already seemed fairly clear: she was one of a dozen or so people in here lined up along the counter with their papers or arguing with their hands, Chinese, Tibetans, Nepalis, Muslims, Kashmiris, a couple of round-eyes, tourists, traders, yak herders, women with braided hair, men with high boots and sashes and daggers, all of them wrapped in shawls and hides and furs against the cold outside. In here it was close to eighty, with two enormous yak-dung stoves burning, smoking the place out. I assumed they'd all been hauled in on some kind of charge: this was a PSB office, where the people on the other side of the counter in Beijing and Shanghai and Chengdu had got their clubs out on that June night and gone to work. There would be a basement under this place, underground cells.