"Don't be silly, Bob," Brains says crisply: "Iris just got word that your fragrant wife has been called away to an incident in Amsterdam and she thought someone ought to keep you company today. The saintly Mo should be back tomorrow; until then, we drew the short straw." He gestures at the beer: "Just like old times, huh?"

"No, it's not just like old times," I snort. Then the penny drops: "Job in Amsterdam . . . ?"

"They needed a lead violin."

"Oh," I say, feeling very small.

There is this about being married to Mo: every few months she gets called to an unexpected job somewhere in Europe, at short notice, with her violin. A philosopher by academic training and a combat epistemologist by subsequent specialization, she doesn't talk about what happens on those trips; but I get to hold her shoulders and calm her when she wakes in the pre-dawn gloom, shuddering and clammy. Years ago, shortly after we first met, we got into a situation where I ended up rescuing her from—well, it wasn't nice, and she overcompensated, I think. The violin's an Erich Zahn original, refitted with Hilbert-space pickups. There's a black-on-yellow sticker on its case that says THIS MACHINE KILLS DEMONS. And sometimes she sits up late into the night, playing music on it that I don't want to think about.

I pick up my phone and thumb-tap back at her: ENJOY AMSTERDAM AND TAKE CARE XXX. Then I put it down carefully, as if it might explode.

Now I've got something to worry about, something to distract me from feeling sorry for myself because of the enquiry, or gnawing over the hollow sense of gnawing wrongness as I see Helen's face melting away in front of my eyes again and again—something tangibly threatening to be upset about. If anything happens to Mo I don't know what I'll do. It's not as if my parents or elder brother know what I do for a living: they think I'm just a junior civil servant. The same goes for Mo, only more so—her dad's dead, Mum's a ditz, and her kid sister's married to an engineer in Dubai. We're isolated, but we can confide in each other, do the mutual support thing that so many couples don't seem to do. We understand each other's problems. Which means that right now I'm drinking for two.

"In the fridge, top shelf on the left, there's an open bottle of wine," I say, standing and making for the cupboard to root out some glasses. "You guys didn't drive, did you?"

"That would be irresponsible, Bob," Pinky says soberly. "Is this the right bottle . . . ?"

"Give it here." I pause for a moment, bottle poised over an inviting glass: "Boris doesn't have anything to do with this, does he? You're quite sure it was Iris's idea?"

"Don't be silly, Bob," says Brains, taking the bottle (and the glass).