Robin looked at her hands on the wheel and remembered that night on the bridge, how Adrian had gripped the rail as if he’d been afraid the Thames churning blackly below would surge up and pull his feet from under him. Alongside the guilt at hurting him there’d run another feeling, one she hadn’t identified until hours later, lying alone in her own bed, head pounding.

He’d taken her for supper at Swan on the South Bank, next to the Globe Theatre. His treat, he insisted. They’d been there on one of their early dates when he’d still been so bizarrely formal, offering to pick her up (she’d always refused, and she’d usually been coming direct from work anyway), dropping her off and asking the cab to wait until he’d seen her safely inside. She’d found it hilarious, the kid-glove treatment: as if she didn’t spend her days dealing with killers.

Their table was a small round one in the corner of a banquette so they sat at right angles to one another, knees bumping. Ade had his back to the window to give her the view, the darkening Thames and the myriad sparkling lights on the other side, the white dome of St Paul’s rising over them like some vision of Ancient Rome. The first time they’d come, she’d loved it but that night, the whole thing had stuck in her craw. Three years earlier, they’d split the bill, she’d insisted, but she couldn’t do that any more. This time, the chic minimalism, all the natural wood and leather symbolized a cosmopolitan world that was no longer hers, and the popping corks were ironic – Oh, well played, Robin! This was for other people now, successful people. She’d watched Adrian hand over his card with a stone in her stomach, felt a wash of relief when the door snapped shut behind them. As the evening had worn on and the other tables had grown louder, she’d started to feel they were laughing at her.

Up on the bridge, she’d stopped to look at the city downstream, the Walkie-Talkie, Tower Bridge, the bright tip of One Canada Square far in the distance. It was the third week of January and the lights looked like decorations left up when the party was over. She was leaving.

He’d turned to face her. ‘Marry me.’

It had been so windy she hadn’t really heard him, or she told herself she hadn’t. She brushed the hair off her face and pulled her beanie down. ‘What?’

He’d had a weird look on his face, half laughing, half frightened, like a child about to do something forbidden. ‘Will you marry me?’

She’d felt her mouth open. Eventually she said, ‘Now?’

‘Well, not right now, obviously – there’s paperwork to do, and I’d like to invite a few people …’