‘I don’t believe memories are gone forever, do you? They’ll come back, Maggie. But they’ll come back when you’re least expecting them. You’ll find they surprise you in ordinary things. It will be a face you see on TV that reminds you of someone. An item of clothing that you wore on the day. A glimpse of your own reflection in a window at night.’

Maggie’s mouth tightened, and the lines round her good eye flattened out in anger.

‘They will come back, Maggie,’ said Fry. ‘Better to let them come to the surface when you can deal with them than to allow them to ambush you when you least expect them. Believe me on this.’

Maggie stared at her. Gradually, her mouth relaxed. ‘Are you talking from experience?’

Fry barely managed a nod. Ridiculously, the simple question had done exactly what she had been warning Maggie against. The burst of recollection was so strong and so physical that she was quite unprepared for it. She had to look away now, and be damned to her determination to look the woman in the eye. She stared at the drapes over the window, counting the brass rings on the curtain rail while she breathed slowly and steadily, counting to three as she inhaled, holding for another count of three, exhaling and counting; holding again.

It only took a few seconds before she was fully under control. She knew there was little outward sign. Most people noticed nothing, certainly her male colleagues. But Maggie was watching her fixedly, in absolute silence. When Fry met her stare again, something had changed. There was an indefinable difference in the atmosphere, as if somebody had just turned on the central heating, and a hint of warmth was beginning to creep into the cold walls.

‘Would you like some coffee?’ said Maggie.

Fry caught a glimpse into a kitchen as Maggie opened the door at the far end of the room. While she waited, Fry looked through her notes, checking the items she had marked for raising in conversation. One thing she hadn’t mentioned yet was Maggie’s family. The closest surviving relative was a sister, who lived somewhere in the west of Ireland.

She watched Maggie pour the coffee from a cafetiere. She wore no jewellery of any kind on her hands – no rings, no bracelet. There was no make-up on her face, either, though it might have helped to hide the scars. She wore no lipstick. Her only adornment consisted of two tiny gold studs in her ears, like miniature crosses.

‘Last time you were interviewed,’ said Fry, ‘you weren’t in a steady relationship, according to the notes. Is that still the case?’

‘Yes.’ Maggie smiled, without humour. ‘They do put everything in my file, don’t they? Yes, it makes life difficult when it comes to forming relationships. Nobody wants to have to look at a face that would frighten the horses.’