Laura told her of the strange man in the park and how she’d thought it was one of Peter’s little jokes to begin with. ‘It isn’t, though,’ she said. ‘I actually asked him – his uncle’s flat has a telephone and I managed to make a call to his base. Fearfully lucky to have got through, and of course I couldn’t stay on the line for long, but I would have felt like a proper twit if I hadn’t asked him. I just laughed and said it didn’t matter, there’s no point in worrying him.’

‘No,’ said Kitty, thinking hard. ‘But if it wasn’t him, then who has sent this?’

‘Exactly,’ said Laura. ‘Who do I know who is away from home?

‘Plenty of people we’ve trained or worked with, or people Peter knows,’ Kitty pointed out.

‘Yes, but who would go to the trouble?’ Laura asked. She paused. ‘Someone who thinks I might believe they’re sick or dead. Someone who wants me to know they’re all right.’ She raised her hands in the air and let them fall again and then blew out a long breath. ‘I’m trying not to get my hopes up …’

‘Oh.’ Kitty suddenly understood. She stared directly at her friend, trying to read her expression. ‘You think it could be Freddy.’

Laura wouldn’t meet her eye. ‘I know it’s unlikely – highly unlikely. But who else do I know who is far from home and cut off and would want to get a message to me like that?’

Kitty knew what she meant and yet didn’t want to give her friend false hope. ‘Laura, it’s been ages. He disappeared before we even met, didn’t he? It’ll be coming on for—’

‘Four years,’ said Laura dully. ‘Autumn 1940, it was. Look, I realise that’s a long time for anyone to be missing and then to suddenly communicate.’

Kitty reached across and took her friend’s hand. ‘It is, Laura. It really is. I suppose anything could happen, but it’s such a long shot.’

Laura shook her head, her usually carefree face now full of desperation. ‘But it might be, mightn’t it? In theory it’s possible, isn’t it? You see why I think I’m going crazy. I’ve been tormenting myself from the moment I saw it. It could just, just be him, alive after all that time.’

Kitty felt unbearably sorry for her friend, and yet she still didn’t feel convinced. ‘Then why now? Why wait for years? It doesn’t really make sense, does it?’