Luke and Mr. Darrow walked out of the whale’s stomach. Ahead of them, the throat stretched into darkness.

“Let’s go!” said Mr. Darrow. “We haven’t got much time!”

He started walking away, then stopped. Luke was standing at the entrance to the whale’s stomach, staring at him.

“Aren’t you going to explain any of this to me? Who you are? What you’re doing here? Why you’re helping me escape? The Great One? Demon?” He paused. “You know—everything?”

Mr. Darrow groaned. “Fine. Mind if we walk and talk? We’ve got a lot to do.”

“Yes!” Luke leapt forward, and the two of them set off, up the whale’s esophagus.

“So, let’s start from the beginning,” said Mr. Darrow. “I made the world, and—”

“Wait—you’re the Great One?” said Luke.

“Yeah, yeah,” said Mr. Darrow. “But don’t go telling everyone. I’ve been trying to keep it quiet. You see, I never meant to create the Floor. It was all an accident!”

He kept walking.

“I’ve been a modeler all my life—and my greatest dream was to build a living model. Nothing fancy: just a little paradise with palm trees, lagoons, a few people, that kind of thing. Something to look after. See, an old man like me, with no family, no kids, you get lonely. And when I heard about this special serum that creates life, I was hooked! One drop, add some light and water, and presto! Tiny, living people! Cool, eh?”

Luke was completely lost. “Er…sure.”

“A lot of people said it didn’t really exist,” said Mr. Darrow. “But I knew that the serum would be out there somewhere. All I needed to do was look properly. And I’m good at looking properly. Finally, after twenty years of searching, I found it—hidden away in the basement of an old abandoned museum in Massachusetts! Can you believe it?”

“What’s a year?” said Luke. “What’s a museum? What’s Massachusetts?”

Mr. Darrow blinked.

“Er…none of that’s important. What matters is that I found the serum. Finally, after five years of building the perfect sandbox paradise, I was ready to add the serum and create a living world!”

He blushed.

“But then I, er…gaffed it all up. I was about to add the serum, and the light in my room switched itself off. I got up to fix it and tripped over a bin in the darkness! I knocked the sandbox paradise to the floor, spilled half the serum on that, and the other half on me. Suddenly I’m shrinking to microscopic size, right in front of my own eyes! Turns out if you get any on your skin, you become tiny too. Who knew?”

Luke still had absolutely no idea what Mr. Darrow was talking about.

“I was pretty hacked off, let me tell you! Looked like I was going to be stuck on the floor forever. My only hope was that Max would arrive. I’d always told him to come to my room if I ever disappeared, so if something went wrong he’d be able to—”

“Max?”

“That giant boy you’ve been talking to this whole time. My apprentice. He’s done a great job, that lad; I’m proud of him.” Mr. Darrow frowned. “Don’t know who the other kid is, though. I’m pretty certain he’s the one who’s been stealing my carrots.”

“Sorry—what are carrots?” said Luke.

“Anyway,” said Mr. Darrow, ignoring him, “Max turned up, just like I’d predicted, but he didn’t see me shouting at him on the floor. Then when he went, he left the bedroom light on…so the serum came to life! All it needs to work is light and water, and the sand was still wet from the tiny lagoon, remember? So the sand spread across the entire floor, thousands of people turned up out of nowhere, and that’s how the Floor was made! Funny story, eh?”

They had reached the start of the whale’s throat. Mr. Darrow glanced over the top of its enormous tongue.

“Humph—looks like the guards are still there,” he muttered. “Never mind. We’ll go out the blowhole.”

He pointed up. Far above them was a tiny opening—a pinprick glimmer in the darkness. Luke could just make out a long rope dangling down from the opening to the throat. Mr. Darrow chuckled.

“And to think—I thought joining up the blowhole and the stomach was a mistake! Still, you live and learn.”

He grabbed the rope and started climbing nimbly up the sides of the whale’s throat.

“But hang on, you’re the Wise Man,” said Luke, following him. “You told everyone that the Great One made the world!”

Mr. Darrow shrugged. “Well, yeah—I knew no one would listen to me if I told the truth. So I sort of made up a story instead. I had to find a way of bringing Max back—he was the only one who’d be able to help me return to normal size before Damon came along and—”

“Damon? Don’t you mean Demon?” said Luke.

“I mean Damon!” said Mr. Darrow. “See? That moron Malcolm wrote down everything wrong in that stupid Book of the Floor!”

Luke gawped. “Malcolm wrote the Book of the Floor?”

“Yeah, yeah,” said Mr. Darrow. “Wouldn’t stop going on about it either.”

He reached the top of the blowhole and heaved Luke out after him. They stood on top of the whale, its backbone stretching away from them like a hillside. The murky green lights of the warflies glimmered on the rubbish around them.

“Damon’s my old boss,” said Mr. Darrow. “A prize moron if ever there was one. I knew if he turned up before Max did, we really were stuffed. He’d hoover us all up without thinking. Maybe even do it on purpose, just to spite me! I had a genius idea for how to communicate with Max, but in order for it to work, I needed the whole Floor working together!”

Mr. Darrow started striding along the whale’s spine. Luke scrambled to keep up.

“You see, Max wears these special earpieces in order to hear. I even put a radio in them once, for a bit of a laugh…and that got me thinking. If I could build a radio transmitter and a microphone, make it slow my voice down and set it to the right frequency, then I could use it to speak through Max’s hearing aid and communicate with him! All the bits and pieces I needed were scattered across the floor—tidiness isn’t exactly my strong point. I just needed to find the right parts.”

The whale’s spine sloped down toward the tail.

“So I told everyone to search the floor for me. I figured that a million hands are better than one, right?” He sighed. “Of course, those idiots all ended up forming into different tribes instead, squabbling over land and arguing with each other. I’ve spent the past eight weeks looking for all the parts myself, and just as I finally finished building the transmitter and microphone, Damon appeared and hoovered us all up!”

They came to the bottom of the whale’s tail and jumped off.

“Now our only hope is to find a way out of here and communicate with Max. If not, then we really are doomed—you know where trash bags get taken, don’t you? Junkyards! If we don’t get out soon, we’re all going to be crushed or incinerated! And the worst part is, I don’t know where my equipment is—it’s lost somewhere in this trash bag!”

Luke turned toward the darkness, his heart pounding. It all made sense to him. This was it. His chance to make up for everything he’d done. His one moment. His destiny.

“Then what are we waiting for?” said Luke. “We’ve got work to do!”

Mr. Darrow looked at him. “What do you mean?”

“We have to overthrow the Bin King!” said Luke. “Reunite the entire Floor! It’s the only way we can save the world—I know it might sound impossible, but nothing is truly—”

“What are you talking about?” said Mr. Darrow. “We’ve done all that already. That’s why I came to get you.”

Luke’s face fell. “What?”

“Ahem.”

Luke turned round. Standing behind him was an enormous warfly, and hanging from its antenna was the Bin King, tied up and groaning. Next to him lay his fly riders, their arms held up in surrender as the Red Queen aimed a sword at their throats. And behind them stood the entire Floor: Reds, Greens and Blues, a million people, united at last.

“What took you so long?”

Luke looked up. Sitting on top of the warfly, looking extremely pleased with herself, was Ivy.