‘It’s just a figure of speech,’ says McAvoy, a little hurt. He wills himself not to blush. He can’t understand why everybody he’s lived with has been so peculiar about such things. If he sees a pile of dishes, he washes them. If the sink needs scrubbing, he scrubs it. If there’s a heap of dirty clothes outside his housemate’s bedroom door, he throws it in the washing machine with his own. That’s considerate, isn’t it? That’s just basic human decency? Wouldn’t that qualify as the absolute least that one person could do for another?

‘And the bath, Hector,’ says Buller, shaking his head and looking at him as if he might be simple. ‘I don’t know why, it’s just weird. You don’t run a bath for your mate. It’s just fucking odd.’

‘You said your back was aching,’ protests McAvoy. ‘I was going upstairs anyway …’

Buller pushes his plate away, tired of explaining the world to somebody clearly born in the cold, icy reaches of another solar system. He gathers up his papers from the floor. Takes a swig of his beer and stifles a belch.

‘Pardon you,’ says McAvoy automatically.

‘For fuck’s sake,’ growls Buller, and polishes off the rest of the beer. He stares into the neck, hoping to refill the bottle with his eye. When a miracle doesn’t occur, he stands up, still snarling, and carries his dirty plates to the kitchen. Bangs them down unnecessarily harshly, then stomps out into the little back yard for a smoke.

McAvoy waits a moment, letting the air in the room regain some sort of equilibrium. Then, gently, he eases back the curtains. Shakes his head, sadly, at the huddled shape of his poor, conflicted associate. He watches, unblinking, as the DC gets comfortable, tucked in against the back wall, cigarette in one hand, phone in the other, perfectly shielded from the wild, sideways rain. McAvoy knows he’ll be there for a while. Keeps watching, just to make sure. Behind him, the tops of the houses start to blend in with the gathering dark. If he listens carefully, he can hear the sound of the droplets hammering on the felted roof of the little shed at the bottom of the yard. The air feels supercharged; static and thick. There’s a crackle to the air; a purplish light seaming the thick, roiling clouds. A storm is coming. A storm that’s going to hit hard.

McAvoy closes the gap in the curtain, puts his book neatly on the floor, and walks as softly as he can to where Buller has left his case notes. He feels a little furtive, a touch deceitful – as if he might be doing something morally questionable. But he’s a police officer, isn’t he? They’re all on the same side, after all. And he knows he’s good at his job – that he sees things that others don’t; that he can make connections and read faces and spot a lie like few others. He doesn’t say any of this out loud: can’t bring himself to blow his own trumpet, but he’s been part of big cases before. Acquitted himself admirably. He’s stopped bad people doing anything worse and he’s helped secure justice for the cruelly bereaved. He might be able to help. He can’t see how he can do any harm. He’s simply sparing the pair of them the awkwardness of having to ask whether it’s OK to look at the case file. He’s sure he’d say yes. So sure, it’s not even worth putting the question.