‘Tell your team. They asked for my alibi last night.’

‘I know. But I told them I didn’t like you for it.’

For fuck’s sake. Robin felt a sudden, dizzying urge to throw everything in the air, jump off the cliff. ‘Well, what if you’re wrong?’ she said. ‘Maybe your judgement’s off. Maybe I was sleeping with my best mate’s husband then got tired of it all and killed the pair of them.’

She glared at him, daring him to say something, but the look of astonishment on his face cut her dead. The burst of whatever it was evaporated in a second, and she felt herself wither inside. What the fuck was wrong with her?

Self-disgust, bitter, and with it, a memory of Corinna’s wedding.

It wasn’t the worst day of her life, but it was top five, even now, probably top three. That had been her fault, too. Rin had tried to protect her – more than tried. In the week before the invitations were posted, she’d gone on and on about it, ringing, sending emails, ‘in case it’s easier to tell me like this than over the phone.’

‘I just want to make sure you’re totally okay with it,’ she’d said. ‘Josh and I are fine – completely fine – if you’d prefer him not to be there. He’s a friend, a good friend, but you’re my matron of honour.’

Some stupid impulse had made her insist it was fine – completely fine – if he was there. She wanted to show everyone that he hadn’t hurt her at all; she’d walked away without a scratch. But more than that, she’d wanted to show him her life. Look at my amazing daughter and my degree and my fast-track job at the Met. I did it! Ha! Without you!

Six weeks before the wedding, however, Rin had turned up on her doorstep in London. ‘There’s been a development,’ she said. ‘He wants to bring someone.’

Everything that had happened in between – the tarting around; the advent of Lennie; her degree; starting at the Met and the unholy logistical hell of just trying to keep it all together – fell away.

‘It might not be serious,’ Corinna said. ‘It’s only new.’

If it had been anyone else, she would have told her to bugger off: why would she care if it was serious? What was he to her? Old history, water under the bridge, bad rubbish. Instead she’d sat on the scratchy sofa with her arms round her knees, silent. Corinna had sat with her.

‘This is not about me,’ she’d said eventually.

‘What?’