Any of the older pubs in the backstreets beyond the river, which draw small groups of resentful locals, men who smoke roll-ups with dead-eyed pit bulls and who will stare at a woman alone in a pub as a mullah would at a woman taking a stroll in a bikini.

Any of the new cheerfully packed drinking places near the river that are packed with people younger than you, mostly groups of laughing friends with Apple Mac satchels and thick black glasses, all of whom will make you feel more lonely than if you had just sat indoors.

 Liv toys with the idea of buying a bottle of wine and taking it home. But every time she pictures sitting in that empty white space alone, she is filled with an unusual dread. She does not want to watch television: the last three years have shown her that this is the evening of cosmic jokes, where normally mundane comedy dramas will suddenly, poignantly, kill off a husband, or substitute a wildlife programme with another about sudden death. She doesn’t want to find herself standing in front of The Girl You Left Behind, recalling the day they had bought it together, seeing in that woman’s expression the love and fulfilment she used to feel. She doesn’t want to find herself digging out the photographs of her and David together, knowing with weary certainty that she will never love anybody like that again, and that while she can recall the exact way his eyes crinkled, or his fingers held a mug, she can no longer bring to mind how these elements fitted together.

She does not want to feel even the faintest temptation to call his mobile number, as she had done obsessively for the first year after his death so she could hear his voice on the answering service. Most days now his loss is a part of her, an awkward weight she carries around, invisible to everyone else, subtly altering the way she moves through the day. But today, the anniversary of the day he died, is a day when all bets are off.

And then she remembers something one of the women had said at dinner the previous night. When my sister wants to go out without being hassled, she heads for a g*y bar. So funny. There is a g*y bar not ten minutes’ walk from here. She has passed it a hundred times without ever wondering what lies behind the protective wire grilles on the windows. Nobody will hassle her in a g*y bar. Liv reaches for her jacket, bag and keys. If nothing else, she has a plan.

‘Well, that’s awkward.’

‘It was once. Months ago. But I get the feeling she’s never quite forgotten it.’

‘Because you are SO GOOD.’ Greg wipes another pint glass, grinning, and puts it on the shelf.

‘No … Well, okay, obviously,’ Paul says. ‘Seriously, Greg, I just feel guilty whenever she looks at me. Like … like I promised something I can’t deliver.’

‘What’s the golden rule, bro? Never shit on your own doorstep.’

‘I was drunk. It was the night Leonie told me she and Jake were moving in with Mitch. I was …’

‘You let your defences down.’ Greg does his daytime-television voice. ‘Your boss got you when you were vulnerable. Plied you with drink. And now you just feel used. Hang on …’ He disappears to serve a customer. The bar is busy for a Thursday night, all the tables taken, a steady stream of people at the bar, a low hum of cheerful conversation rising above the music. He had meant to go home after he finished at the office, but he rarely gets a chance to catch up with his brother, and it’s good to get a few drinks in now and then. Even if you do have to spend your time avoiding eye contact with 70 per cent of the customers.

Greg rings up some money and arrives back in front of Paul.

‘Look, I know how it sounds. But she’s a nice woman. And it’s just horrible having to fend her off all the time.’

‘Sucks to be you.’

‘Like you’d understand.’

‘Because nobody ever hits on you when you’re with someone. Not in a g*y bar. Oh, no.’ Greg puts another glass on the shelf. ‘Look, why don’t you just sit her down, tell her that she’s a really lovely person, yada yada yada, but you’re not interested in her that way?’

‘Because it’s awkward. Us working so closely together and all.’

‘And this isn’t? The whole “Oh, well, if you ever fancy a quickie when you’ve finished this case, Paul” thing.’ Greg’s attention shifts to the other end of the bar. ‘Uh-oh. I think we’ve got a live one.’

Paul has been dimly aware of the girl all evening. She had arrived looking perfectly composed and he had assumed she was waiting for someone. Now she is trying to climb back on to her bar stool. She makes two attempts, the second sending her stumbling clumsily backwards. She pushes her hair out of her eyes and peers at the bar as if it’s the summit of Everest. She propels herself upwards. When she lands on the stool she reaches out both hands to steady herself and blinks hard, as if it takes her a couple of seconds to believe she has actually made it. She lifts her face towards Greg. ‘Excuse me? Can I have another wine?’ She holds up an empty glass.

Greg’s gaze, amused and weary, travels to Paul and away. ‘We’re closing in ten minutes,’ he says, flicking his tea-towel over his shoulder. He’s good with drunks. Paul has never seen Greg lose his cool. They were, their mother would remark, chalk and cheese like that.

‘So that leaves me ten minutes to drink it?’ she says, her smile wavering slightly.

She doesn’t look like a lesbian. But, then, few of them do, these days. He doesn’t say this to his brother, who would laugh at him and tell him he had spent too much time in the police.