She felt an urge to complete the story. ‘I tried to phone the number too. Just got a voice message saying it was unobtainable. Looking back, I guess he was using a burner phone and instantly dumped the SIM card.’

‘Probably,’ he replied. ‘That’s the only sure-fire way, now and then, to be anonymous on a mobile. Any other way’s traceable.’

She frowned. ‘How do you know that?’

‘It came up when I was searching how Morahan’s text to you could have disappeared.’

She relaxed – they were back in the present. ‘That reminds me, I must lend Buttler my phone to sort that one out.’

‘Are you sure you need to?’ He paused. ‘After what’s happened today.’

‘Yes,’ she said firmly. ‘I want the doubts gone.’

They fell into silence; the last secret between them was out.

Or so it seemed to him. She thought of telling him about the recent anonymous texts, but what was the point now? Particularly the last one she’d received seven hours ago in the stables:

Someone you want to see will meet you at the barn. You must vacate around 4 p.m. for thirty minutes to allow their arrival.

The real reason she’d lied about the phone signal, prompting the drive from the farm to find one.

Should, could she have shared it with Patrick? To find out the burner phone number Patrick had got her for this trip, they, whoever they now were, had either, as Kareem implied, tracked every one of Patrick’s preparations for the trip or, as he’d feared, monitored her morning call to the hospital switchboard. The extent of the surveillance might have panicked him.

In addition, if she’d shown it to him without further explanation, he too perhaps would have realised it could only mean that Kareem was not dead but alive, wanting a final showdown with her. He would have insisted on pulling her out, putting his duty to protect her above all else, failing to understand that she could not – and would not – run away from it, nor from the opportunity to bring him to justice, however hopelessly that had turned out.

It was pointless too to tell him. She had a powerful sense that there would be no more anonymous texts. Even if it had begun with Kareem, she had come to wonder if there was an additional guiding hand. She might never know who that was. She must try not to think about it, it would achieve nothing.

The silence she was crowding with her internal arguments began to oppress her. ‘What are we going to do about today?’ she finally asked.

‘He had some nerve, didn’t he?’ said Patrick. ‘Why show at all? Why say what he did.’