The ghost must have sensed the strike gathering, because she turned and flew at me like a bullet. Her mouth opened in a scream, and I could see jagged, pointed teeth lining her jaws, the empty white fire of her eyes.

" Fuego!" I shouted, and then the spirit hit me, full force. A beam of white fire spewed out from my blasting rod and across the wooden storefronts. They burst into flame as though soaked in gasoline. I went down, rolling, the spirit going after my throat with her teeth. I jammed the end of the blasting rod into her mouth and prepared to fire again, but she tore it from my hands with a ferocious dog-like worrying motion and it tumbled away. I swiped the staff at her awkwardly, to no avail. She went for my throat again.

I shoved a leather-clad forearm into her mouth and shouted, "Michael!" The ghost ripped at me with her nails and clamped down on my forearm. I dropped the ghost dust and scrabbled furiously at her with my free hand, trying to lever her off of me, but didn't do much more than muss up her clothing.

She got her hand on my throat and I felt my breath cut off. I writhed and struggled to escape, but the snarling ghost was a lot stronger and faster than me. Stars swam in front of my eyes.

Michael shouted, and swept Amoracchius at the spirit. The great blade bit into her back with a wooden-sounding thunk and made her arch up, screaming in pain. It was a deathblow. The white light of the blade touched her spirit-flesh and set it alight, sizzling away from the edges of the wound. She twisted, screaming in fury, and the motion jerked the blade from Michael's hands. Agatha Hagglethorn's blazing ghost prepared to fly at his throat.

I sat up, seized the sack of ghost dust, and with a grunt of effort swept it at the back of her head. There was a sharp sound when the improvised cosh struck her, the superheavy matter I'd enchanted hitting like a sledgehammer on china. The ghost froze in place for a moment, her feral mouth wide-and then toppled slowly to one side.

I looked up at Michael, who stood gasping for breath, staring at me. "Harry," he said. "Do you see?"

I lifted a hand to my aching throat and looked around me. The sounds of baying hounds and thundering hooves had gone. "See what?" I asked.

"Look." He pointed at the smoldering ghost-corpse.

I looked. In my struggles with Agatha's ghost, I had torn aside the prim white shirt, and she must have ripped up the dress when she'd been crashing through sidewalks and strangling wizards and so on. I crawled a bit closer to the corpse. It was burning-not blazing, but steadily being eaten away by Amoracchius's white fire, like newsprint slowly curling into flame. The fire didn't hide what Michael was talking about, though.