He had broken every rule of undercover ethics: He’d kissed her, fucked her, made promises to her. He had let her stand naked in front of him, let her show him photos of Billie as a baby, let her fall in love with him, even though her heart was already broken. And he’d barely told her a single honest thing about himself.

He’d sworn to keep her safe, promised that one day they’d go away together, somewhere far from Nottingham and all the things that had happened to her. He’d half meant it, too, even though he’d known simultaneously that it was impossible. He’d told her he loved her—and maybe that was the one truthful thing he’d ever said to her, but even that wasn’t a pure truth.

And, above all, he still hadn’t quite trusted her. He’d succumbed to a creeping suspicion that she might know more about what had happened to her daughter than she was letting on.

Those trips she’d started taking, slipping off early evenings once or twice a week. By then Paul had known the smell of her hair after a shift in the café; the lullabies she’d sing when she was sad; the way she’d fiddle with her left earring when nervous—particularly around her brother, it had always seemed. But he’d had no idea where she went on those just-popping-out-for-a-bit nights.

In a way, it had redressed the balance. She’d known nothing real about him—she thought his parents were dead, that he had always done odd jobs for a living—so perhaps it was only fair she had her secrets too. But Paul couldn’t have let the mysterious outings pass without investigating them, especially when he’d noticed Daniel slipping her money before she left. It had been his duty to find out what she was doing. Or so he’d told himself many times since.

Paul closed his eyes and saw the remote outbuilding he had followed her to one night. His heart pumped as hard as it had at the time, watching her go in, fearing the worst about whom she might be visiting. He’d experienced a brief flutter of excitement at the prospect of a breakthrough in the case he’d nearly lost hope of solving, but it was quickly drowned in dread. Nathalie couldn’t be involved. It was supposed to be Daniel, not her. She was innocent, and she would be free once they’d exposed her brother. That was what he’d clung to throughout their relationship.

The other times he’d followed her, he had hidden much better. That time, perhaps he’d subconsciously wanted her to see him. He’d been so desperate to know what was inside that building, what she was doing there.

And, of course, when she’d spotted him on her way out, she’d wanted to know the same.