Perhaps it was a silly idea, but Diana was always trying to figure out ways to give Constance a greater sense of independence. Rational as the decision had been to put those locks on the doors, they weighed as much on Diana’s conscience as they played on Constance’s nerves. She went to one door or another half a dozen times a day to test them, and each time she did, Diana had to explain again why they were locked.

‘Never mind,’ Constance said, as if it to comfort Diana, ‘my real prison is trusting you.’

The phone rang.

‘Merry Christmas,’ Diana said into a good deal of static.

‘Merry Christmas to you,’ said a pleased Jill.

‘Where are you?’

‘In Mexico.’

‘Having a good time?’ Diana asked, amused.

‘Passable. How about you?’

‘David gave us a new compact disc player.’

‘A what?’

‘A new sort of record player. It’s marvellous.’

Constance came into the kitchen, drawn by the ringing of the phone.

‘How’s Constance?’

‘Here she is to tell you herself,’ Diana said. ‘It’s Jill in Mexico.’

Jill was the only person Constance could be persuaded to talk to on the phone. Her side of the conversation didn’t make consecutive sense, but Diana knew it was the sound of that voice, still with traces of a London accent, which Jill had phoned to hear, and she would contrive to make Constance laugh at least once.

Constance brought her amusement to the breakfast table, no longer aware of its source.

‘Ham for breakfast? You’d think it was Christmas!’

‘It is,’ Diana said.

‘So it is,’ Constance said, consulting the heading on her memory board, and then she looked down at the timer hanging around her neck. ‘And I’m to go off at intervals all through the day.’

‘Well, try it anyway,’ Diana said, ‘but not today. You won’t need it today.’

Her real gift to Constance was to be with her all day and to treat the time as if it were as rare and special as it had been all those years ago when they had to spend so much time apart, when they were never without the anxiety that something might happen to either of them before they could meet again.

The compact disc player came as a new surprise to Constance. For Diana the sound, of such intense purity, recalled the first concerts she had gone to with Constance, music which seemed charged with erotic energy, as defiant and glorious as Diana felt herself in love. It was as if she had never before really listened or, for that matter, looked.

Poor as Constance’s childhood had been, she had not been deprived as Diana had been, growing up at the pioneer edge of the world. The museums and libraries were free, concerts and theatres cheap.

‘I seduced you with London,’ Constance had been fond of teasing.

‘You didn’t need London,’ Diana always replied.