"Fatal accidents never happen because of just one mistake," I try to explain. "It takes a whole chain of stupids lining up just so to put a full stop at the end of an epitaph."

"So what did you do afterwards?" she asks quietly.

"Afterwards? It was too late to do anything." I shrug. "I told 'em not to disturb the scene and called the Plumbers. Then I had to wait until they arrived and hang around while they logged the scene and filed a preliminary report and bagged the body, which took all evening. They had to use a Dyson—there wasn't enough left of her to fill a teacup, never mind a reanimator's workbench. It's on the books as a level four excursion, incidental unintended fatality. The desk officer was very understanding but I've got a ten o'clock appointment with someone in Operational Oversight to file an R60." An official incident report. "Then I suppose there'll be an enquiry."

And the juggernaut of an internal investigation will start to roll, bearing down on my ass like hell's own lawn mower in search of an un-trimmed blade of grass, but it's not as if I don't deserve it. I take another sip of the whisky, wishing I could drown myself in it. This isn't the first time I've killed someone, but it's the first time I've killed a civilian bystander, and I lack the words to express how I feel.

"I was going to dump on you," Mo tells me, "but . . . forget it." She empties her glass and I realize that while I was seeing that purple light the whisky has evaporated from my tumbler. "Come to bed now."

I push myself to my feet, neck drooping. "It won't make things better."

"No."

"I feel like shit."

"No, Bob, you need to get some sleep."

"I am a shit."

"You need to get some sleep. Come to bed."

"If you say so."

I follow her upstairs. Today's been shit, and tomorrow is quite possibly going to be worse—but it can wait for a while.

2. POINTING THE FINGER

I GO TO WORK IN A NONDESCRIPT OFFICE IN CENTRAL LONDON, south of the river and east of the sun—I can't say precisely where—located above a row of shops. It's a temporary home for the department, and it's officially called the New Annexe, probably because it was thrown up in 1964. It consists of three floors of characterless sixties concrete piled up above a C&A and a couple of other boring high street stores like a bad perm on a grocer's granny; it used to belong to the Post Office, back in the day. And nothing you can see through the windows from outside is really there.