Soon she was ushered into a side office where Anderson and the press officer went over with great patience what she would need to say and before she knew it she was hurried into another, larger room, a mic was fitted to her top and she was directed towards a bank of tables in front of a blue screen, the Met’s insignia at its centre. She sat between DCI Carter and DS Anderson, TV cameras pointed at her, a sea of eyes trained on her face. Mac stood to the side, and she tried to keep the reassuring warmth of him in her mind while she stared ahead, saying her piece to the cameras. But despite her determination to hold it together, to somehow compel a watching stranger to reach out and help, to make this horrible nightmare end and bring Luke safely back to her, her words stumbled and she clenched her fists so hard she thought her knuckles might burst through the skin.

Afterwards, when the ordeal was finally over and she and Mac were standing outside the station doors staring back at each other, she found she was shaking so violently that Mac had to reach out and clamp her arms firmly to her sides. ‘I’m so sorry, Clara,’ he said miserably, ‘I’m so fucking sorry you’re having to deal with this.’

She looked dazedly back at him. ‘Mac, I wouldn’t be able to cope with any of it if it wasn’t for you.’

He hugged her then, wrapping her tightly in his arms and when they drew apart he exhaled a long breath. ‘Come on,’ he said, ‘let’s get the fuck out of here and have a drink.’

It made the national news later that night. Clara was sitting on Mac’s sofa, half-heartedly picking at some pasta he’d made for her when Luke’s face suddenly loomed large on the TV screen. She cried out in shock, causing Mac to rush in from the kitchen and together they watched in silence.

‘Fears grow for missing London man, Luke Lawson,’ the newsreader said. It was the picture she’d taken of him herself earlier that year, at a bar in King’s Cross where they’d all gone to celebrate his twenty-ninth birthday, and for a moment she was back there again, tasting the tequila shots, laughing as the whole bar joined in with an impromptu round of Happy Birthday. Luke smiled back at her from the TV screen with joyful, blameless eyes.