«Dear, dear, Fox,» she chided as she waggled a finger in his face. «Try to be careful.» Taking his wrist lightly between her thumb and forefinger, Rivi moved his hand so the grinder pointed its stream toward the floor. «As I said,» she smiled, glancing back at us, «the dust doesn't affect me. My wee tricks aren't magic – psionic powers use a different type of energy.»

«Fire is energy too,» the Fox announced.

Rivi patted his arm. «Keep an eye on our guests, darling. I'll be back in a while.»

She turned away and began to walk in the direction of her own quarters. Dust spilled from her clothes with every step. Part way across the machine room, she looked back and called, «Heel!» Obediently, the squad of wights lined up and traipsed after her. Petrov, too, followed along; the flesh of his arm had burned away, but the blazing scepter remained in his hand, fused solidly with the bone. Any normal man would have passed out long ago from the pain. I could only assume Rivi was keeping him conscious with the power of her mind.

She waited for Petrov to catch up, then wafted a caress under his chin. «You'll be ever so handy come nightfall, darling – I'll use you as a lamp.» Laughing, she strode from the room, with the wights and the fire-ravaged Petrov shuffling along behind her.

«Well,» said Yasmin to the Fox, «time for you to let us out.»

«Can't,» he replied. «Not supposed to.»

«But it's fun to be bad,» Kiripao told him. «Don't you like being naughty?»

The Fox smiled and nodded.

«Then let us out,» Kiripao said.

«Can't,» the Fox replied. «Not supposed to.»

«If I were Rivi,» I murmured to the others, «I'd dance all over the old barmy's brain to make sure he always follows orders. He's too unreliable to trust otherwise.»

«Agreed,» Oonah nodded. «I doubt if he's capable of disobeying her directly. We'll have to try something more subtle.»

I bowed slightly to her and leaned back against a dust-covered control console. Watching a Guvner be subtle could prove immensely educational.

«Fox,» Oonah called, «talk to me. You've got us at your mercy, right? This is the time when it's traditional to gloat about all your plans.»

«Hah!» he replied. «Shows how much you know. Rivi never tells me her plans.»

«But you must have a little information… like why you were attacking the various faction headquarters in Sigil.»

«Oh that.» The Fox stuck out his tongue in distaste. «Rivi just wanted to bob all the records from the last expedition to come here. How to reach the Glass Spider, how to steer it, where the grinders were… boring stuff. If it weren't for me setting fire to things, we wouldn't have fun at all.»

«And how do you like to have fun?» Oonah asked.

«Burning things, of course. This white dust is supreme. Setting all the magicians and priests on fire… isn't that a laugh?»

«I certainly would like to see you set something on fire,» Oonah said. «What do we have handy that would burn well?»

«That gnome of yours looks pretty flammable…»

«No, no,» Oonah shook her head, casting a quick glance back at Wheezle. Our Dustman friend had made no effort to get to his feet since the blast from Unveiler had blown him against the wall; I hoped he was simply conserving his strength. «Let's see what else there is,» Oonah continued. «I'm sure you shouldn't damage any machinery… or any of us… so we're really just left with that useless chunk of wood right there.»

Of course, she pointed to the heavy beam blocking the door.

The Fox stared at it suspiciously. «I don't know…»

«Oh, you don't think you could burn it?»

«Of course I can burn it!» he snapped. «But…»

His brow furrowed, as he struggled to understand whatever misgivings he had. In a way, I felt sorry for the old barmy: his mind must be fragmented beyond recovery, broken by whatever hell he had experienced long ago. Once, he must have been a formidable man – Oonah's mother wouldn't have adventured through the planes with a weakling – but now he was simply a mad old twitch, falling for a trick that wouldn't fool a child.

«I don't think you can burn it at all,» Oonah said sharply, not giving him time to recognize the trick. «I think your flame has gone out.»

«Gone out!» he roared. «I've got a flame the size of a bread loaf!»

And with a bellow of arcane syllables, the Fox loosed a fireball at the beam.

Shooting a fireball precisely is like throwing an elephant from a catapult – you've got plenty of margin for error, but there's going to be a splash. In this case, the splash hit the outer wall of the control room, giving those of us inside a view of angry red brilliance; then it bounced back into the machine room proper, washing gouts of flame across the collection of pistons, gears, and camshafts gallumphing through their regular paces.

Sturdy though the mechanisms were, they weren't designed to withstand a sudden fiery blast. A cog blew off a spindle; the spindle sagged into the path of a flywheel; the flywheel flew off its mount, and churned whackety-whack through the outer plate of a boiler; and then there was steam everywhere, spurting from the boiler in scalding high pressure clouds.

«Oopsy,» said the Fox. He threw himself under the control desk where Hezekiah had found Oonah's staff.

It was high time we vacated the premises; yet despite the pyrotechnics, Fox's fireball hadn't completely scragged the wooden beam. Yes, its exterior was charred and crumbly, but the flash-fire hadn't penetrated the heart of the wood. Kiripao threw himself at the door with all his strength… and he bounced back with a bruised shoulder. Perhaps if we all put our backs to it, the obstruction might yield eventually; but before we could try, Oonah waved us away.

«We can't waste time,» she shouted. «Stand back.»

As she raised her ice-staff, I shouted, «Don't do it!» She did it anyway.

A split-second before the staff fired, it blazed as bright as the sun. Oonah's clothes instantly burst into flame; but her hands didn't waver an inch as she trained the tip of the staff at the door in front of her. A solid battering ram of ice shot from the staff, hissing as it contacted the fires around Oonah's body. Hot melt-water spattered us all; yet the flames only thawed the outer layer of ice, leaving the ram with enough mass to smack against the door with the sound of thunder.

The wooden beam shifted a scant two inches.

Screaming defiance, Oonah fired again. Another burst of magic-fueled heat exploded around the ice-staff, far too much to withstand so soon after the first flames. The staff vaporized in her hands, blazing so blindingly bright I couldn't see the result of Oonah's shot – my vision washed out in a blur of searing brilliance. Still, I heard the boom of impact, then the crunch of timber breaking to flinders. The door slammed open, letting in a rush of steam from the broken boiler.

Oonah took one step toward the doorway, then dropped to her knees. The white dust fire had taken a terrible toll – none of the victims I'd seen at the courts had been so viciously burnt. Her clothes were gone, her skin now as black as charred wood. Kiripao leapt forward to hold her up… and as he grasped her hand, it broke off at the wrist, like a twig reduced to ash.

«Go,» Oonah said, her voice nothing but a whisper. «Stop Rivi. Preserve justice.»

And she toppled forward, a dead and crumbling thing.