The question they had to answer was quite simple, and they had been told by the seneschal that he had been told that it was an empirical question, not a purely theoretical one, though he had also said he found this difficult to believe, as even the mysterious powers and forces which moved the Wars themselves could not control such absolutes... The question was: What happens when an unstoppable force meets an immovable object?

Simple as that. Nothing more complicated or obtuse; just that. Ajayi thought it was a joke, but so far all the castle's inhabitants, all the attendants and waiters, one or two other subsidiary characters they had discovered, the seneschal himself, and even the ever-facetious rooks and crows which infested the decaying upper storeys had treated the question with extreme seriousness. That really was the riddle, and if they got the answer right they would escape from the castle, be taken from this limbo and resume their duties and positions in the Therapeutic Wars again, debt paid.

Or they could kill themselves. That was the unspoken alternative (or at least unspoken by all except the red crow, who cheerily brought the subject up on every third or fourth visit), that was the easy way out. It was a long drop from the balcony of the games room; the castle apothecary carried a line of lethal poisons and draughts; there were ways out of the castle, a postern or two, and a narrow winding path through the fractured rocks and fallen masonry all tumbled round the castle's plinthed base like scree, then a long cold walk into the snowy silence...

There were times when Ajayi considered that way out; not as attractive then and there, but for when - if - there ever seemed to be no hope, at some time in the future. Even so, she found it hard to imagine ever becoming so desperate. Time would have to drag on a lot longer than it had, she would have to get a lot more fed up and tired with this old, time-frozen body before suicide became a serious alternative. Besides, if she went, Quiss would be abandoned. The self-destruction of one partner meant that the games could not go on. The other one could not play on alone or find somebody else to play, and if the games could not be played and ended, the riddle could not be answered.

"Ah... excuse me..." They both turned to look at the winding-stair door, where the small attendant was peeking round the side, most of its body hidden in the twisted darkness beyond.

"What?" Quiss said.

"Ah... sorry..." the attendant said, in a small voice.

"Eh?" Quiss shouted, his voice altering in pitch. Ajayi took a deep breath and sat back on the stool. She'd heard. She thought Quiss had too, but he didn't want to admit it to himself. "Speak up, you wretch!" Quiss roared.

"That wasn't it," the attendant said, staying in the doorway. Its voice was still small; Ajayi found herself straining to catch its hesitant words; "that wasn't the right answer. I really am -"

"Liar!" Quiss rose off his seat, shaking with rage. The attendant yelped and disappeared. Ajayi sighed. She looked up at Quiss, who stood, fists clenched, glaring at the distant, empty doorway. He turned, whirled round to look down at her, the scraps of fur around him flying out. "Your answer, lady," he shouted at her, "your answer; remember that!"

"Quiss -" she began quietly. He shook his head, kicked the small chair he had been sitting on, and marched off across the squeaking, grating glass floor, heading for his own apartments. Before he left the games room for the short corridor which led to his rooms, he stopped by the side wall of the room, where more conventional paper and cardboard books lined the slate fabric of the castle - the masons" lame attempt at insulation. Quiss clawed at the wall, tearing the faded, yellowing books away from it, throwing them behind him like a dog digging a hole in the sand, bellowing incoherently and tearing and swiping at the wall, baring the green-black slate beneath as the torn, ripped pages fluttered away behind him, falling to the grimy glass floor like some flat, grubby snow.

Quiss stormed off, slamming a door somewhere, and Ajayi was left alone. She walked over to where the just-savaged books lay strewn across the floor, and stirred them with the toe of her boot. Some of the languages she knew, she thought (it was hard to tell in the uncertain light, and she was too stiff to be bothered bending down), and some she did not recognise.

She left the pages where they lay, one-dimensional flakes littering the murky floor, and she went to stand by the balcony window again.

Against the unending, unaltering whiteness of the plain, a flight of dark birds flew. The same sky looked down, blank and forgettable and grey, itself unchanging.

"And what next?" she asked herself in a low voice. She shivered and hugged herself tighter. Her short hair refused to grow any longer, and her furs had no hood. Her ears were cold. What was next, they knew already from the castle seneschal, was something called Open-Plan Go. Goodness knew how long that would take them to work out and play, assuming Quiss came back from his sulk. The seneschal had muttered something about this next game being the closest analogue of the Wars themselves, which worried Ajayi for a start. That sounded awfully complex, and long.

She had asked the seneschal where the ideas for these odd games came from. He said from a place which was the castle's chosen Subject, and had hinted, she thought, that there was another way to get to this place, but refused to be more specific. Ajayi was trying to cultivate the seneschal's acquaintance (when her sore leg and stiff back let her get down to the basement levels where he was usually to be found) whereas Quiss had started out trying to intimidate him. When the man had first arrived he had tried to torture information on how to escape from one of the waiters. It hadn't worked, of course, just made the others frightened.

Ajayi's belly rumbled. It must be mealtime soon. Waiters would appear shortly, if they weren't too frightened of Quiss being in a bad mood. Damn the man.

Open-Plan Go, she thought, and shivered again.

"You'll be saw-ree!" croaked a passing rook, cruising past on black wings and using the voice of an old, bitterly remembered lover.

"Oh, shut up," she muttered, and went back inside.

On the bridge which carried Rosebery Avenue over Warner Street, there was a smell of paint. Black dust lay on the pavement, collecting in the spaces of the bridge's primed balustrade. Graham hoped they would paint the bridge tastefully. He looked into the cradle the painters were using to paint the outside of the balustrade from, and saw an old radio so spotted with paint it could have been an exhibit. The man in the cradle was whistling to himself and coiling a length of rope.

Graham felt oddly satisfied at seeing life go on around him like this; he felt almost smug at walking past people and them not giving him a second glance, at least not now he'd got rid of Slater. He was like some vital cell in the bloodstream of the city; tiny but important; a message bearer, a point of growth and change.

She would be waiting for him now, getting ready, perhaps only now getting dressed, or still in the bath or shower. Now at last it was coming out right, the bad times were over, Stock deposed. It was his time, his turn.

He wondered what she thought of him now. When they had first met she thought he was funny, he guessed, though kind too. Now she had had time to get to know him better, see other sides of him as well. Perhaps she loved him. He thought he loved her. He could imagine them living together, even marrying. He would make a living as an artist - probably just a commercial artist at first, until his name became known - and she could do... whatever she wanted.