‘Splendid,’ said Ghorr. ’What are they doing, Ullii? Surely they know that locking themselves in is useless?’

‘Breaking the floor,’ said Ullii with lowered head.

‘Reinforce the mancers just outside the door,’ snapped Ghorr to a messenger, who hurried away. ‘Captain,’ he turned to a hulking officer, each of whose intricately tooled military boots could have accommodated Ullii’s head and neck, ‘lead us to the room below Flydd’s. Bring two squads. Fusshte, take a third squad down the far stairs and cut off the other exit.’

Ghorr allowed his troops to take the lead, then caught Ullii’s arm and hauled her down the stone staircase. As they crossed a landing, a muffled roar shook the building.

‘Quick, Captain!’ said Ghorr. ‘Flydd’s broken through. Take him and Irisis alive and there’ll be a bonus for you.’

The soldiers hurtled down the steps, swords raised. Ghorr kept well back. The chief scrutator guarded his life like a miser his hoard.

They reached the bottom step, rounded the corner and there, in the flickering light of the soldiers’ torches, stood the fugitives. Irisis had stopped dead when she saw the soldiers, then raised her sword. Flydd glanced over his shoulder at the cluster of dancing torches and his skinny shoulders sagged. Scrutator Fusshte and his heavily armed troops blocked the only way out.

Ullii lifted her mask for a moment. Xervish Flydd, a small man of some sixty years, looked more scarred and emaciated than ever. Though it was bitterly cold, he wore just a bedsheet, hastily knotted about his hips. Beautiful Irisis Stirm was dressed in brown woollen pantaloons and a loose shirt which could not conceal her luxurious figure. Her yellow hair was unbound. They were both covered in grey dust.

Ullii pulled the mask down, as if to hide from her former friends, but Flydd had already seen her. He shook his head, a moment of desolation, and Ullii knew she had done a terrible wrong. But what else could I do? she thought plaintively, slipping into the shadow behind Ghorr before Irisis could see her.

‘Xervish Flydd,’ said Ghorr in a treacly voice. ‘Irisis Stirm. I’m so pleased to see you both again.’

Irisis shifted her weight, holding the sword two-handed, but Flydd drew her back. ‘There’s no point, Irisis. Put it down.’

After a long hesitation, she let the sword fall. The soldiers took hold of the pair and swiftly bound their hands.

‘These are the last,’ said Fusshte. ‘Let’s get the trials underway, Chief Scrutator. The executioners grow impatient.’

‘The executioners wait upon my pleasure,’ Ghorr said icily. ‘Take the prisoners out to the yard, Captain.’

Ullii pressed back into a niche in the wall, hiding from herself. Flydd had let her down, certainly, but he’d been kind to her too, and always looked after her. And she’d betrayed him to a monster.

Taking off the mask, she rubbed her eyes, trying to work out where it had all gone wrong. As Flydd was dragged past, his eyes met hers for a second. He knew Ullii had betrayed them; he was looking right into her heart and, worst of all, he understood.

The guard jerked on the rope; Flydd stumbled away. Ullii crouched down in her niche, shivering violently. Cold rarely bothered her but now she felt like a statue carved of ice. She was just as bad as Ghorr.

Irisis was dragged past. Hastily pulling down the mask, Ullii turned her face to the wall until the crafter had gone by. Irisis would neither understand nor forgive.

The troops led their prisoners upstairs, gloating and calculating their shares of the reward, and getting in vicious blows when Ghorr wasn’t looking. Ullii remained where she was. Ghorr took little notice of her at the best of times and, now that he had his enemies at his mercy, would not give her a moment’s thought. It was easy to conceal herself in the darkness, for no one was more skilled at hiding than she.

She slipped into a room that had already been checked while Fiz Gorgo was searched one more time. Finally, the soldiers tramped out into the yard. The scrutators had gone. Ullii tracked the knots they made in the eye of her lattice. They went out through the broken front doors of Fiz Gorgo and up onto the outer wall, from whence they were hauled up in rope chairs to the comfort of the hovering air-dreadnoughts, doubtless to indulge themselves in an orgy of congratulations. The prisoners and their guards were left to shiver in the ice-crusted yard until the preparations for the trial were complete.

Fiz Gorgo was silent now. Ullii put her head out the door. The darkness was comforting and she felt the lattice strengthen a little, but she had lost her purpose. Seeing Flydd that way had thrown her. Then a familiar tang raised bumps on her arms. Nish!

She tasted the air, nose up like a mouse. To Ullii, Nish was his smell, and she could have identified him anywhere. She’d picked him out from sixty thousand soldiers and slaves when he’d been sentenced to haul bogged clankers out of the sodden battlefield at Snizort last summer.

There was a trace of his spoor down here, though the scent was old. On the ground floor it had been stronger. Ullii took off the mask and earmuffs. Her sensitive eyes could see well enough in the dark, not that she needed to. She eased up the farther stair, the one Fusshte had come down. The stench of him drowned out all other smells: stagnant water in the flooded labyrinth below, mould growing on the walls, the faint odour of woodworm and rotting timber, and even the unwashed, sweaty reek of the soldiers. Fusshte had a sour, festering stink that made her nostrils pucker and her toes curl.

It was brighter on the ground floor. A gloomy daylight seeped in through the broken front doors, though it cast little light around the corner to this narrow hall. The breeze was blowing away from the doors and she could not tell if Nish was out there. Dare she look? Easing to the shattered remnants of the great doors, Ullii covered her eyes with her fingers and peered out.

She didn’t see Nish. The prisoners were kept apart, save for Flydd and Irisis, and each was surrounded by burly guards. All the men of Ghorr’s guard were tall and Nish, a small man, would not be visible behind them.

Ullii went back and forth, testing the air for every tendril of odour, and, around the corner, picked up an old scent. She could even tell that Nish had been weary when he’d come this way. He’d plodded down the corridor before stopping for a moment. Why? Ullii smelt Irisis’s fresh, creamy tang and her fists clenched involuntarily. Nish and Irisis had been lovers once, before Ullii had met him. She sniffed the air. He’d gone into her room!

She tracked him to the bed and he’d been in it. He’d lain with Irisis just hours ago. How dare he? Ullii didn’t operate on logic – as far as she was concerned, Nish had been hers ever since they’d made love in the balloon in the treetops near Tirthrax, at the end of last winter. He’d made her pregnant there, and even though he’d killed her brother since then, she would share him with no one.

It firmed her faltering resolve. She tracked Nish to his little room. The bed was cold but a fresher scent led around the corner, into the main hall and up in the direction of the front door. There she lost it.

Ullii crept along the hall on her toes, keeping to the left-hand wall, ready to dart away should someone approach. She could hear the guards talking in the yard, gravel crunching under their boots and an occasional mutter or plea from the bound prisoners, always answered with a jeer or slap.

She headed for the stairs to one of the tower balconies she’d seen from Ghorr’s air-dreadnoughts, so she could look down into the yard. A few steps up, she detected Nish’s spoor once more, and it was fresher. He’d gone this way in the last few hours.

Unfortunately he’d come down again; she smelt him on the other side of the staircase as well. Nonetheless, she continued up to a landing on the second floor, where she went down on her belly and crawled to the edge. The scent was stronger here. He’d spent some time with the tall mancer she now knew to be Yggur.