But Clara wasn’t listening. ‘Emily? This is Emily?’

Tom looked back at their astonished faces in surprise. ‘Well, yes. Of course it is. Why? Who did you think it was?’

‘But I’ve met Emily,’ Clara said, her voice rising in panic. ‘This isn’t …’

‘You’ve met …?’ He stared at her. ‘No, you haven’t. She disappeared almost twenty years ago. How could you possibly have met her?’

She glanced around at Mac, but saw he was looking now for something in his bag. ‘I was contacted by someone who said they were Emily,’ she said, turning back to Tom. ‘I met up with her in a bar, she came to my flat. If this is Emily, then who have I been meeting?’

They stared back at each other.

‘Clara?’ Mac had pulled out his laptop and was turning it on. He brought it over to them. ‘This is the person you’ve been meeting, isn’t it?’ She looked down at the laptop screen, and there was a picture of Emily, or at least the person who’d said that she was. It was a slightly blurred photo taken of her profile, surrounded by a crowd of people.

‘Where did you get this?’ she asked Mac.

He flushed and looked away. ‘I took it. When you said you were going to meet her in the bar that first time …’ He met her astonished gaze. ‘I was worried!’ he said defensively. ‘I know you didn’t want me to come with you, but I needed to make sure it wasn’t a trap, that you weren’t meeting someone dangerous. I’m sorry. I waited in a doorway down the road from the bar, then when she left you I followed her to see where she was going. It all seemed so suspicious.’

Her eyes widened. ‘So I did see you that night! I thought I’d imagined it.’ She turned back to the picture. ‘Where did you follow her to?’

‘Shoreditch Tube. I had my Leica around my neck as usual. When she was buying a ticket, I took a picture of her but she turned around and saw me. I just brazened it out and kept walking, got on the Tube and went home.’

Clara stared at him in horror. ‘What camera did you say it was?’

‘The Leica, the one that—’

‘Went missing from your flat?’

‘Yes.’

‘Could she have followed you home that night?’

He thought about it. ‘I suppose. I didn’t see her, but it was busy, rush hour, there were a lot of people.’

‘So she could have followed you. She could have broken in later and stolen it from your flat, knowing you had her picture stored on your camera?’

He looked at her. ‘Yes, I suppose so,’ he said.

‘So if this person isn’t Emily,’ Clara said, ‘then who the fuck is she? Who have I been meeting with?’