It took almost an hour before Ian caught her alone. ‘Kate,’ he said. ‘I hope you’re bearing up.’

By this point, Kate had consumed quite a few glasses of Simon’s fine champagne. A few too many. ‘What are you doing here, Ian?’ she asked.

‘Just wanted to support you, old girl.’ Ian was drinking squash and he swirled the remnants in his glass, then drained it. He’d thrown a jacket over his habitually casual attire, but he still looked like an overgrown student.

‘That’s too kind of you,’ she said.

‘Now, now. My secretary told me your mother had passed away. I knew you had a complicated relationship with her. I thought it might be a good idea to come and offer some moral support. After all, the Service owes you a great debt.’

Kate didn’t know where to begin to dice this unlikely explanation for his presence here. ‘It’s decent of you,’ she said easily.

‘How are you?’ he asked. ‘We didn’t really get to the bottom of that the other morning.’

‘Fine.’

‘We have a duty of care, as you know, not only during the years of employment, but afterwards, too. So if there’s anything I or we can do together, don’t hesitate to let me know.’

‘I will, thank you.’

Kate was about to break off and go in search of more congenial company when he leant in closer. He had never been one to respect anyone else’s personal space, especially when it came to the women he worked with. ‘I just wondered what you were up to,’ he asked.

‘In what sense?’ Kate was distracted by the sight of Sir Alan and Rose in deep conversation in the corner. She recalled the scarf she had seen in Sir Alan’s house. Could it possibly be that Rose had also travelled down to see him that day and, if so, why?

‘Well, I’m aware you left under something of a cloud. I’ve not had any other employer approach me to check a reference, which I have, of course, promised to provide. So I was just keen to ensure you’re getting along okay.’

‘I’m fine, thank you.’

‘Good. Good.’ He nodded. ‘As I said, very happy to provide that reference – and even to help you find a job in the private sector if that would be helpful.’

‘But?’ she said. ‘Because I’ll take a wild guess that there is a “but” here.’

‘I’d obviously wish to know if you were stepping back into territory that might impinge on our interests.’

‘Your interests singular, or plural?’

‘Well, without being pompous, dare I suggest it’s the same thing?’

‘Congratulations on your elevation, by the way,’ she said. ‘You’ve certainly earned it.’

Ian smiled at her. ‘Characteristically ambiguous. I like that. And punchy as ever.’

‘Get to the point, Ian.’

‘That was the point. If there was a chance you might step on my toes, I’d like to know about it. I think you owe me that.’

Kate was minded to say she didn’t owe him a damned thing, but as she broke away from the conversation all she could think about was who had tipped him off about her investigation. His wife, Shirley Grove, Julie?