‘Do you know what it’s like to live for thirty years with a secret like that, of them doing … whatever they did? Now do you see why I said nothing? Did nothing?’ She prodded herself in the chest with a stiff finger. ‘I can’t prove anything.’ One prod per word. ‘I couldn’t save her. I couldn’t find her. If they would do that to her, what do you think they might do to me? To my son? Just because I’m married to their boss doesn’t mean they wouldn’t do whatever they had to, to save themselves.’

She paused for a moment. ‘My husband can be a hard man, Detective. He wouldn’t have got to where he is by going easy on people, but he would never condone hurting Natasha.’ A little strength crept back into her voice. ‘Never.’

She stared at Porter, daring him to contradict her. He didn’t believe for a second that Locke was squeaky clean, but he begrudgingly conceded to himself that she could be right about this much. If it had been Natasha, it sounded like whatever happened had already taken place before he drove out that night – not that this would condone any part in covering it up. James Bolton had been involved with Natasha not long before she disappeared. They could prove he had been in her flat. Was he so focused on nailing Locke that he risked overlooking the glaringly obvious? Violence followed James Bolton. Had for years. If even half the stories about him were true … One thing at a time. Focus on what happened to Natasha, for now at least. Whatever Locke was up to, his time would come, and soon. If Porter could take his right-hand man out of action, that would be a big fuck you to Locke and his whole operation.

Decision made, he took a deep breath. Refocused on Natasha. ‘So the tree is what, then, nothing?’ Hope seeped away like a slowly shrinking balloon as he said it.

A firm shake of her head. ‘It’s something, to me at least. There’s not a day that has passed I haven’t wondered if I could have done something that night, or any of the days that followed. It was somewhere to go when I hated myself for being weak. Somewhere to go to say sorry. Somewhere I could find again if I needed to.’

That made sense. The tree stump he had used himself as a marker – it had guided her back time after time, year after year, for apology after apology.

‘I looked for a sign, any sign of where she might be. But after a while, it was enough just to be there.’

Porter sat back, calculating odds of success from what they had. ‘Mrs Locke, we need to find her. We need you to make a statement and we’ll go back there and find her.’