Eva saw the black and white barrier at the frontier rise up and watched first one, then the two other cars cross safely over the border to Germany.

Eva sat still behind her tree for a while, emptying her mind as she had been trained: there was no need to move, better to pause rather than do anything sudden or rash, storing away the details of what she had seen, going back over the sequence of events, making sure she had them correct, reminding herself exactly of the words she and Lt. Joos had said to each other.

She found a path through the wood and walked slowly along it until she came to a forester's dirt track which led her in time to a metalled road. She was two kilometres from Prenslo, the first signpost she came to informed her. She walked slowly down the road towards the village, her mind full of noisy and competing interpretations of everything she had witnessed. When she reached the Hotel Willems she was told that the other gentleman had already left.

BERANGERE CALLED IN THE morning to say she had a bad cold and could she cancel her tutorial. I acceded immediately, sympathetically and with some secret pleasure (as I knew I'd still be paid) and decided to take the opportunity of two free hours and caught the bus into the town centre. On Turl Street I stepped through the small door into my college and spent two minutes reading the notices and posters pinned to the big board under the vaulted gatehouse before going into the porters' lodge to see if there was anything interesting in my pigeon-hole. There were the usual flyers, Middle Common Room sherry-party invitations, a bill for wine I had bought four months previously and an expensive white envelope with my name – Ms Ruth Gilmartin MA – written in sepia ink by a very thick-nibbed pen. I knew instantly who was the author: my supervisor, Robert York, whom I regularly traduced by referring to him as the laziest don in Oxford.

And, as though to punish me for my casual disrespect, I saw that this letter was a subtle reprimand – as if Bobbie York were saying to me: I don't mind your taking me for granted but I do ever-so-slightly mind your telling everyone that you do take me for granted. It read:

My dear Ruth,

It has been some time since last we caught sight of each other. Dare I ask if there is a new chapter for me to read? I really think it would be a good idea if we met soon – before the end of term if possible. Sorry to be a bore.

Tanti saluti, Bobbie

I called him immediately from the phone box in the lodge. He took a long time to answer and then I heard the familiar patrician basso profundo.

'Robert York.'

'Hello. It's me, Ruth.'

Silence. 'Ruth de Villiers?'

'No. Ruth Gilmartin.'

'Ah, my favourite Ruth. The prodigal Ruth. Thank the Lord – you gave me quite a nasty turn there. How are you?'

We arranged to meet the following evening at his rooms in college. I hung up and stepped out into the Turl and paused for a moment, feeling oddly confused and guilty all of a sudden. Guilty, because I had done no work on my thesis for months; confused, because I was now thinking: what are you doing here in this smug provincial town? Why do you want to write a D.Phil, thesis? Why do you want to be an academic?…

No quick or ready answers came to these questions as I plodded slowly up Turl Street towards the High – contemplating going to a pub for a drink instead of returning home for a frugal, solitary lunch – when, as I passed the entrance to the covered market, I glanced over and saw an attractive older woman emerge who looked remarkably like my mother. It was my mother. She was wearing a pearl-grey trouser suit and her hair seemed blonder – recently dyed.

'What're you staring at?' she said, a little crossly.

'You. You look wonderful.'

'I'm in remission. You look terrible. Miserable.'

'I think I've reached a crossroads in my life. I was going to have a drink or two. Care to join me?'

She thought this was a fine idea so we turned about and made our way to the Turf Tavern. It was dark and cool inside the pub – a gratifying respite from the brazen June sun – the old flagstones had been recently washed and were mottled with moisture and there were very few customers. We found a corner table and I went to the bar and ordered a pint of lager for myself and a tonic water with ice and lemon for my mother. I thought about the latest episode in Eva Delectorskaya's story as I set the glasses down, tried to imagine my mother – then virtually the same age as me – watching Lt Joos shot to death before her eyes. I sat down opposite her: she had said that the more I read the more I would understand – but I felt a long way from comprehension. I raised my pint glass to her and said cheers. 'Chin-chin,' she said, in return. Then she looked at me as I drank my beer, puzzled, as if I were slightly deranged.

'How can you drink that stuff?'

'I got a taste for it in Germany.'

I told her that Karl-Heinz's brother, Ludger, was staying with us for a few days. She said she didn't think I owed the Kleist family any more favours, but she appeared unconcerned, even uninterested. I asked her what she was doing in Oxford – usually she preferred to do her shopping in Banbury or Chipping Norton.

'I was getting a permit.'

'A permit? What for? Invalid parking?'

'For a shotgun.' She saw my face move into a rictus of incredulity. 'It's for the rabbits – they're ravaging the garden. And also, darling – I must be honest with you – I don't feel safe in the house anymore. I'm not sleeping well – every noise I hear I jerk awake – but really awake. I can't get back to sleep. I'll feel safer with a gun.'

'You've lived in that house since Dad died,' I reminded her. 'Six years. You never had any problems before.'

'The village has changed,' she said, darkly. 'Cars drive through all the time. Strangers. Nobody knows who they are. And I think something's wrong with my phone. It rings once then cuts out. I hear noises on the line.'

I decided to act as unconcernedly as she had. 'Well, it's up to you. Just don't shoot yourself by accident.'

'Oh, I know how to use a gun,' she said, with a small self-satisfied chuckle. I decided to say nothing.

She rummaged in her bag and produced a large brown envelope.

'Next instalment,' she said. 'I was going to drop it off on the way home.'

I took it from her. 'Can't wait,' I said, and it wasn't, for once, a flippant remark.

Then she covered my hand with hers.

'Ruth, darling, I need your help.'

'I know you do,' I said. 'I'm going to take you to a proper doctor.'

For a moment I thought she might hit me.

'Be careful. Don't patronise me.'

'Of course I'll help you, Sal,' I said. 'Calm down: you know I'll do anything for you. What is it?'

She turned her glass around a few times on the table-top before she answered.

'I want you to try to find Romer for me.'

Ostend, Belgium. 1939

EVA SAT IN THE agency's conference room. A heavy squally shower was passing, the smatter of rain making the sound of fine thrown gravel against the window panes. It was darkening outside and she could see the buildings opposite all had their lights on. But no lights were lit in the conference room – she was sitting in a curious premature winter afternoon's dusk. She picked up a pencil from the table in front of her and bounced its rubber end on her left thumb. She was trying to keep the image of Lt Joos's boyish run across the car-park at Prenslo out of her mind – his fluid easy sprint and then his fatal stagger and stumble.