‘Ginny Parris,’ he said, reading aloud, ‘with two Rs. She was a hooker who worked the backstreets off Atlantic Road. Bit of a local landmark, by all accounts. “She didn’t use nothing any more - she was clean for six months now. She used to work for Red Paul, but since he went down she looks after herself, doesn’t she? She’s not stupid.” That ringing endorsement brought to you courtesy of Pauline “Exotique” O’Malley, Miss Parris’s former colleague, at her business address behind the Mercury cab rank on the Brixton Road.’

He put the notebook back in his pocket, his sombre face contrasting with the flippant tone of his summary.

‘It wasn’t a man who did this,’ I said, stating the obvious.

‘No,’ Gary agreed. ‘It wasn’t. Not unless he put that thing through her with a siege catapult.’ He was momentarily distracted by a uniformed constable who was about to move a table out of the way of a bunch of white-coated lab-rats. The table was probably the source of the murder weapon, because one of its legs had been broken off. It lay at an oblique angle, reminding me faintly of a dying horse in a Sam Peckinpah Western. ‘Oi!’ Gary yelled at the plod. ‘Don’t touch a bloody thing until it’s been dusted and logged. Didn’t your mum teach you anything, you plukey little gobshite?’

The constable blanched, mumbled an apology and backed hurriedly out of Gary’s line of sight, where he probably relieved his feelings with an obscene gesture or two.

‘No,’ Gary said again, returning his attention to me. ‘The working hypothesis is a loup-garou. Which is one reason why you’re here, Castor. If whoever did this was undead, you can presumably tell us what size, brand and flavour it was. And then you can toddle off home to bed, which is obviously where you’ve come from.’

I put a hand up defensively to my stubbled chin. Okay, so I looked like I’d been rolled up wet and put away dry. But I wasn’t on the force, I was just a civilian adviser, so Gary could go fuck himself. He couldn’t exactly put me on a charge for letting the side down.

‘Didn’t have to be were-kin,’ I mused aloud. ‘Could be a geist, or a zombie.’ Neither of those options sounded right, though. A poltergeist powerful enough to do something like this would have left the air saturated with its presence. Even the Thomases - exorcist hate-speak for rationalist sceptics - on the Met would feel like they were breathing cold shit soup. And most zombies are weaker than humans, not stronger: they can push themselves a little harder, because their pain-pleasure wiring collapses after a while, along with the rest of their nervous system, but this was way outside the normal range of activity for a dead-man-walking.