“And anyway,” Deeba said, “Curdle and the rebrella are coming with me, and they might get homesick.”

“You can’t let feral rubbish cross into London,” Mortar said anxiously. “It belongs in another world.” Deeba looked at him and raised an eyebrow, and his voice dried up. “I suppose one or two can’t hurt,” he mumbled.

“So listen,” Deeba said. “I’m not saying good-bye to any of you. I’ll say ‘See you soon.’ And I mean really soon. Let me explain.

“I told you one reason the Smog grew so strong: ’cause it was getting help. There’s one thing we haven’t dealt with. Mortar, you said the police burrower was gone?”

“Yes. We checked where you said it had been. The officers must have got out and fixed it, gone home yesterday.”

“Right. They threatened my family. It might have been only to scare me— there’s nothing in it for them to actually do anything now. But I don’t like it. And I don’t like who they ally with. For the sake of me, and my mate Zanna, and my family, and London and UnLondon, it needs sorting. So I wanted to make a suggestion. An arrangement. It’s going to involve clearing some rubble in Unstible’s old place, but I think it’s worth it.”

Deeba looked at them all. Jones cracked his knuckles and raised an eyebrow. Hemi pursed his lips thoughtfully. Deeba smiled.

When evening fell, with a huge grinding, the UnLondon-I spun once more. With focus and effort, Mortar and the Suggesters directed the bridge.

Deeba hugged every one of her friends good-bye.

“Oh,” she said to Hemi. She fumbled in her pocket.

“Tell me you ain’t reaching for that money,” he said. She grinned.

“It’s no good to me, ” she said, and held it out. “You might as well…” He took her hand gently, and closed her fingers back over it.

“This way you still owe me,” he muttered. “So this way you got to come back, to pay up.”

Deeba swallowed and nodded and hugged him again. She held her breath, and turned and ran to the edge of the bridge. There was a strain, an effort, a whining in the air, and Deeba felt a membrane split, somewhere in reality. The bridge dipped across the Odd. She ran towards the walkway by her front door, which she could see beyond the girders.

I dunno what might happen, she thought, giddy, head spinning. I could go back. I could live there, in a moil house with walls made out of wallets and windows made out of glasses. Or in a house like a goldfish bowl. I could catch a train from Manifest Station.

But right now…

She stepped off the bridge, and breathed deeply in the London night. She looked all around her. Curdle exhaled at her feet. Deeba smiled.

“Hush,” she told it. “And you.” She held up the rebrella. “Remember. Over on this side, when other people’re around, you stay still.”

She turned. The bridge still soared out across the estate. Standing near its edge, waving at her, were her friends. Joe Jones; Skool; Hemi the half-ghost, biting his lip; Bling and Cauldron, their bodies quite solid; and Obaday Fing, carrying the book.

Deeba blinked through tears and smiled. She raised her hand. The UnLondoners waved back. She and they looked across at each other, from city to abcity.

A cat yowled somewhere. Deeba glanced in its direction.

When she looked back, the Pons Absconditus was gone. Deeba stood alone on the concrete walkway, in the dark. In London.

Deeba gave a long, shaky sigh. She picked up Curdle, put it in her bag. She whispered to the rebrella: “Remember!”

Then she turned and unlocked her front door.