‘I think it’s time you tell me what we’re doing here,’ Ben said, as he pulled the car into an empty space in the cemetery car park.

Kate gazed out of the window at the rolling green hills stretching to the horizon. White frost still dusted the grass around the small stone chapel behind them, where the sun had failed to reach. This was the first time she’d been back to Sunbury in the last year.

Ben killed the engine. ‘Well?’

Kate’s eyes lingered on the landscape a moment longer, before turning to face him. ‘How much do you know about why I left London?’

His eyes narrowed. ‘You’ve never wanted to discuss it, and I figured it was best not to push you. Is that why we’re here? Is this where… is this where that young DC is buried?’

Kate nodded. ‘Her mother owns a place nearby.’ She took a deep breath. ‘It’s my fault she’s dead.’

She could see Ben wanted to offer reassurance, but he kept his lips tight and allowed her to speak, knowing she would only tell him as much as she wanted to.

‘We were hunting for a killer: a monster who had already assaulted and butchered three women across London. I was leading the investigation, but in the months since the first victim had been discovered, we were no closer to identifying who it was… I was under so much pressure to find a breakthrough. The tabloids were phoning our comms team hourly for updates. The story was everywhere; people were terrified. All we knew was single women were being targeted.’

Kate stared out of the window, trying to distance herself from the memory. ‘It wasn’t until the third victim that we found a connection: they’d all had profiles on online dating sites – never the same one – but each had uploaded a profile in the three months prior to their deaths. We subpoenaed each site’s records trying to find the one person who’d been in contact with each of them, but there were no matches. We didn’t tell the public about the connection, as we didn’t want to cause more hysteria. Instead, we… I decided to put one of our officers undercover as a singleton looking for love. It was like casting bait into the sea, hunting for a rare breed of fish.

‘She was such… a bright and brave detective. I recognised her passion and fight to prove herself. I never really expected we’d snare him, but…’ Kate pulled her hands across her face, conscious that she’d shared more than she’d intended. ‘Anyway, that was a year ago, the least I can do is pay my respects to her.’ She opened the car door and eased her swollen foot out.

Ben touched her arm tenderly. ‘Do you want me to come with you?’

She couldn’t face him; he’d already done too much. ‘No – thank you. I need to do this alone.’

Kate forced herself up, closing the door with her crutch, shivering against the wind and tucking the small bunch of petrol-station flowers under her arm, before making her way up past the chapel.

She hadn’t been welcome at the official ceremony, her bosses at the Met warning her to keep away ‘for the sake of the family’. They’d made her the scapegoat in a situation that had grown beyond her control as Senior Investigating Officer. Amy’s family had wanted someone to blame, and her colleagues at the Met had thrown her under the bus, making false promises about how a more experienced SIO would bring about justice for their daughter. Twelve months on, and the investigation hadn’t progressed. Despite everything that had happened, she desperately hoped that tonight’s Crimewatch reconstruction would shed fresh light on the murders. Even if she wasn’t the one to catch the killer herself, at least knowing that he’d been found would bring some peace to her.

She reached the summit of the hill, and rested the blooms she’d bought against the gravestone. Saturday was the official anniversary date, and she anticipated there would be more mourners here then, but she didn’t want to cause further pain by paying her respects then.

Reading the inscription on the stone, Kate bowed her head. ‘I think about you every day,’ she said quietly. ‘I replay the events of that night over and over in my mind, and I still don’t know what I could have done differently. I’m so sorry… I won’t ever stop until I catch him.’

A sudden gust of wind caused the bunch of flowers to topple. Balancing on one of the crutches, Kate stooped to pick them up again and didn’t hear the woman approaching from behind until she spoke.

‘You’re not welcome here.’

It was said so matter-of-factly, without a trace of emotion, but Kate recognised the rich Belfast accent immediately.

She straightened and turned. ‘Mrs Delaney, I didn’t think—’

‘Be gone now, you hear.’

‘I understand your—’

‘I don’t want your sympathy, or your pity. I don’t want anything from you.’

‘I – I just came to pay my respects.’

‘Will you just go?’

Kate pressed her crutches into the grass, but the right one slipped on the mud, and before she could correct her balance, she crumpled to the ground. She looked up at the woman dressed head-to-toe in black to see if she would at least offer her a hand, but Erin Delaney couldn’t even look at her.

Kate rested on her elbow to catch her breath. ‘I would do anything to trade places with her. You must realise that I never meant for Amy to get hurt? I didn’t want her to go undercover, but she was so keen to prove herself, and to honour her father’s name. She volunteered. I know I should have been stronger and rejected her request, but that wouldn’t have been fair on her. You will never know how sorry I am for what happened.’

Erin bent down and looked Kate in the eye. ‘You allowed that bastard to take my little girl. If you want forgiveness, you’re looking in the wrong place.’ She picked up the bunch of flowers and threw them at Kate’s feet. ‘You’re not welcome here, Detective Inspector Matthews. Leave my family to mourn in peace. Don’t come back.’

A figure appeared by Erin’s side. Kate recognised him as Amy’s stepdad. He nodded towards Kate, but made no effort to help her up. ‘I think you should go, detective,’ he said, no resentment in his voice, just a statement.

Kate watched the woman kiss her palm and rub the tombstone before the couple made their way further into the graveyard. The wind blew against the bitter sting of tears, but Kate willed herself not to crack. She would save her mourning for later, for when she was alone; her heartache wasn’t welcome here, and she owed them that much at least.