0f all the bizarrities that Frannie had experienced on this journey none was quite as shocking to her as stepping over the threshold of the Domus Mundi with Rosa. To be standing in daylight one moment surrounded - as far as her naW a senses were concerned - with grass and sky, and the next to be in a dark, poisonous place with the sun gone, and the sea gone: it was terrifying. She was glad she had Rosa with her, or she'd certainly have panicked, and this would not be, she thought, a good place to lose your self control.

Rosa demanded to be set down once they were in the House, and went with a few stumbling steps to the nearest wall. There she passed her hands over the surface, leaning a little closer to sniff at it. 'Shit,' she said. 'He's covered the wall in shit.' She called to Frannie. 'Is it all like this?'

'As far as I can see.'

'Ceiling the same?'

Frannie looked up. 'Yes.' Rosa laughed. 'Is it different from the way you remember it?'

'I don't much trust my memories, but I don't think it was a sewer when I was last here. Rukenau must have done this.'

She started to probe the wall with her fingers, pulling away cobs of filth once she had her fingers deep enough. There was a source of light beneath the excrement, Frannie saw; a luminescence which seemed to ripple as Rosa worked, as though it sensed somebody was labouring to unveil it. This was no illusion. The larger the hole Rosa tore in the wall became, the more apparent the muscular motion in the light. And there were colours in the brightness; brilliant darts of turquoise and tangerine. The caked dirt was no match for this energy, now that it sniffed its liberation. What had first been a rain of small cobs of filth rapidly escalated, as Rosa's labours inspired the light to shake itself loose. Cracks spread up and out from the place where Rosa had begun, the caked soil losing its grip as word of revolution spread.

Frannie watched astonished as the process unfolded before her, and not for the first time on this journey wished Sherwood could have been at her side to share the sight. Particularly this: his Rosa, the woman he'd idolized, turning her hands to such transformative labour. Frannie felt blessed to witness it.

And as more and more of the mystery that Rukenau had concealed came into view, Frannie began to make some fledgling sense of its nature. The colours that gleamed and shone in the wall were hints of living things. Nothing whole yet, but enough intimations: a flicker of stripes on a pulsing flank, the glitter of hungry eyes, a spreading canopy of wings. Nor were these presences going to be readily restrained, that much was already apparent. They were too vital; too eager. The more ambitious of them were spreading into the room, spilling the echoes of their forms into the grateful air, like sparks flying from an uncontainable fire.

'Help me up,' Rosa demanded, and Frannie duly went to her aid, though she did so without looking at Rosa, she was so enraptured by the spectacle of burgeoning forms.

'We have to go and find Rukenau,' Rosa said, her thin fingers digging into Frannie's shoulder. She reached up and touched Frannie's face. 'Are you looking at the world?' she said.

'Is that what this is?'

'This is the Domus Mundi,' Rosa reminded her. 'And whatever you're seeing now, there's far finer to see. Now come on, I need your strength a little while longer.'

She didn't need to be carried any more; she had clearly gained some measure of vigour from being in the House. But her sight was not restored, and she needed Frannie to lead her, which Frannie was happy to do. By the time they had crossed the first chamber into the room beside it, the message of rebellion had overtaken them. A dry rain of soil particles started to fall upon them as cracks opened in the vaulted ceiling; and the room was already brighter than the space they'd left, the blaze flickering from fissures on every side. There were sounds rising to accompany the spectacle; though like the first hints of sight they were at present undifferentiated, a murmur from which now and then a more specific noise would come. An elephant trumpeting, perhaps; a whale making song; a monkey howling in a churning tree

But Rosa heard something closer to her heart.

'That was Steep,' she said.

There was indeed a human voice, afloat in the brimming sea of sounds. Rosa picked up her pace, the same word coming with every breath:

'Jacob. Jacob. Jacob. Jacob.'

Will couldn't see what was happening between Rukenau and Steep they were too far from him, their struggle obscured by the ropes - but he saw the consequences. The structure, for all its complexity, had not been built to withstand the struggle now going on in its midst. Ropes were being pulled from their roots in the wall, bringing clods of dead earth with them. Light and motion were coming in their stead, illuminating the spreading collapse. Places where the burden of furniture was the heaviest were the first to go. A table came crashing down, claiming two of the more substantial platforms as it fell, delivering them all in splinters to the shaking ground. There were fissures here too, and shafts of roiling brightness coming to swell the sum of light. More than light, life. That was what Will saw in the swathe of unfurling colour: the throb and shimmer of living things.

As the ropes and platforms continued to fall, he had sight of Jacob and Rukenau. They looked, he thought, like something Thomas Simeon might have painted: two spirits engaged in a life-and-death struggle on the shaking heights. Rukenau was by no means accepting his fate. He was using his ease amongst his perches to keep his body out of Steep's way. But Jacob wasn't going to be denied his quarry. Without warning he dropped to his knees and caught hold of the precarious lace of rope on which they swayed, and shook it so hard that Rukenau pitched forwards. Will saw Jacob's knifehand rise up to meet the other man's chest, and though he couldn't see the weapon Will knew by the shriek escaping Rukenau's lips that the blade had found its home. Rukenau started to topple; but as he did so caught hold of his executioner, so that they both fell, locked together, dividing the mesh with their combined weight as they hurtled to the ground.

The House shook. Rosa stopped in her tracks, and uttered a little sob. 'Oh now...' she breathed. 'What have you done?'

'What's happened?' Frannie said.

She got no answer, but she no longer needed Rosa to locate Steep, because she heard him for herself, his voice unmistakable.

'Finished now, are you?' he was saying, 'are you finished?'

Rosa was stumbling ahead of Frannie, who followed her through a narrow door into a rubbish-filled passageway. Several times Rosa fell as she scrambled towards her destination, but she was up the instant after, and out of the passageway now, with Frannie on her heels, into Rukenau's chaotic chamber.

Will caught a motion out of the corner of his eye, and was vaguely aware that somebody had entered, but he could not unglue his gaze from the sight on the ground long enough to see who it was.

Jacob had got to his feet, and was tearing at the ropes that had caught about him as he fell. Rukenau had no hope of rising ever again, however. Though he was still alive, his body twitching, Jacob's knife was buried in the man's body, and blood was coming from the wound in copious amounts. His filthy shirt and waistcoat were already completely soaked, and the blood was now pooling around him.

Will was still outside Jacob's field of vision, but he knew he would not remain so for very long. Once the Nilotic looked his way, it would come and finish its threatened work. Though it was hard to look away, he turned his back and slipped off, choosing as his means of exit the door through which Ted had disappeared in pursuit of his wife. Only once he reached it did he think to look back across the chamber at those who'd lately entered, and there saw both Frannie and Rosa. Neither had eyes for him. Both were looking at Rukenau's cavorting body.