Carter took the Watchers down, down, down, until they reached the lowest level of the Under. They said nothing for a long time, afraid that their voices might carry and give them away. All the while, Ben listened for sounds of pursuit and the chilling calls of the Feathered Men, but they never came. They had given the Legionnaires the slip.

“I hope Valentine was lucky too,” said Ben.

“We weren’t lucky,” Carter contradicted him. “It was my knowledge of the Under that enabled us to outfox our dull-witted trackers.” He sniffed. “I’m certain Valentine’s equally superior understanding of the complexity of these tunnels will have allowed him to keep the escapees out of harm’s way. No doubt they are already tucked up in a Watcher safe house.”

“I wish we could say the same for Mr. Moon and Ghost,” said Ben. He couldn’t shift the image of the shaven-headed Watcher being snatched away from the escape tunnel before he got a chance to descend. Maybe that was a good thing, considering what happened to the shaft a second later, but even so the knowledge that their friends were still prisoners of the Legion weighed heavily on him.

Experience had taught Ben that things never quite turned out how you planned. As if to prove his point, the ceiling above their heads suddenly groaned, releasing a shower of mortar and fragments of brick. They could all see it; the rainwater that had saturated the soil and collapsed the escape tunnel was wreaking havoc on the fabric of the Under.

“I never thought I would see the Under like this,” said Carter, as they waded along another dark corridor. He sounded almost melancholy. “One of the unseen architectural wonders of the world, as important as the pyramids at Giza or the lighthouse at Alexandria.”

“A rat’s nest is a rat’s nest, whatever you call it,” said Lucy.

“Can art only be made by good men then, Miss Lambert?”

Lucy shrugged. “I don’t know about that, but I know that dungeons and torture chambers aren’t on my list of great achievements.”

They fell into silence again. With every weary step the flood water dragged at their legs and sucked the warmth from their blood. And they still had such a long journey to make.

They had decided to return to Mr. Smutts’s. Since the Legion had already searched there and found no sign of the Watchers – thanks to Hans – it made sense that the Legion wouldn’t think of looking there again. That meant that they had to trek from one side of London to the other, all the way back to Old Gravel Lane. It was miles.

They trudged onwards, each lost in their own thoughts.

“You know that the Legion will have doubled the guards on the detention camp now,” said Nathaniel. “I don’t see us being able to break in a second time.”

“We might not have to,” said Lucy. “Just as your tunnel broke the surface, Mickelwhite was gathering victims to take part in a ‘circus’, whatever that means. Mr. Moon broke the captain’s nose and Ghost was caught trying to escape – you can bet your life that Mickelwhite will want to punish them for that.”

“A circus?” said Ben. “What’s that all about?”

“History holds all the answers, Ben,” said Carter. “Do you know how the Roman Emperors held on to their power?”

Ben shook his head.

“With bread and circuses.”

“I don’t understand,” said Nathaniel.

“Free bread and free beer,” Carter explained, “so the masses had something in their bellies, combined with gruesome spectacles to keep them entertained.”

“Gladiators versus lions?” Ben gasped.

“Something like that.”

“Wherever they are, we need them and we’re going to find them,” said Ben.

Carter drew in a breath as if to say something and then thought better of it. Instead they all kept their thoughts to themselves and concentrated on putting one foot in front of the other.

A day, a lifetime, later, Carter brought them to a halt beneath a manhole cover. The professor climbed up the iron ladder and cautiously lifted the heavy lid. The storm-laden sky was dark and Old Gravel Lane was eerily quiet. The curfew bell had rung and the street was deserted. Motioning for the others to follow, Carter hauled himself out onto the cobbles, his eyes constantly searching for danger.

Ben knew that they had to get under cover before they could breathe again, but as he lifted his face to the rain he found an unexpected grin forming on his lips. He nudged his brother in the ribs affectionately.

“We’re home,” Ben whispered. There was the Jolly Tar, the pub where he used to go and buy books from Jago Moon before it all began. There was the spire of St Peter’s, stretching up into the stormbound sky…

There were faces looking at them from behind filthy windows.

“Quick!” said Ben, the smile gone. “The Smutts’s place is just up here.”

Hugging the shadows, the Watchers followed Ben. Just a little further…

Ben’s hopes came crashing down. They had arrived at Mr. Smutts’s house but there was no refuge to be had here. The windows were all broken. The door had been smashed off its hinges. A message had been scrawled along the wall in blood-red paint – Watchers beware!

Ben staggered to a halt, uncertain of which way to turn. His heart ached in his chest; after all the kindness that family had shown him…

An image of them flashed through Ben’s mind – filthy and miserable inside the detention camp. With difficulty, he shook the thought from his head. They had to keep moving; make it to safety; make it to Revolution Day.

“What shall we do, Ben?” Lucy hissed.

“I don’t know,” said Ben. “But we can’t stand here—”

“Psst!” called a voice from the gloom. There was something familiar in its bronchial wheeze that gave Ben hope. He turned. Standing in a doorway, beckoning with a tobacco-stained hand, was a shabby, unshaven man.

“This way, hurry,” said the man in a rich Polish accent. He smiled, displaying an uneven row of brown stumps.

“Mr. Wachowski!” Ben exclaimed, greeting the old man who had lived in the basement back in the day when the Kingdom family had rented Mrs. McLennon’s freezing attic room on this very street.

The man bustled them in through the doorway, which, like his teeth, had presumably once been white and shiny. “I have new lodgings, yes,” Mr. Wachowski exclaimed. “Mrs. McLennon turned me out on the street.”

“I know the feeling,” said Ben, standing shivering in the man’s corridor.

“I never knew why,” Mr. Wachowski continued, then paused to dredge phlegm up from his rattling chest and spit it roughly in the direction of a rusting spittoon.

“A complete mystery,” muttered Carter, following them inside and closing the door behind him.

Mr. Wachowski drew the bolts across the door and then led them into his room. It was tiny, filthy and cold. A meagre fire struggled in the grate. A single chair that clearly doubled as a bed sat in the corner, its horsehair stuffing spilling from a dozen tears. Mr. Wachowski drew the flimsy rags that counted as curtains across the window, and pushed his chamber pot out of sight under a stained table. The contents slopped alarmingly.

“Make yourself at home,” said Mr. Wachowski. “So, you’re famous now, Ben Kingdom. Lucky I found you, eh?” He paused to hawk up another mouthful of mucus. “Everyone in London knows your name and, to think, I knew you when you were this high.” The old man’s eyes glowed warmly. “Sit,” he said. “Rest, please.”

Ben didn’t need to be asked twice.

The floor suddenly seemed to be as comfortable as a feather bed, and as he flopped down, Ben felt the arms of sleep wrapping around him. In the moment before his eyes shut, he saw Lucy and Nathaniel were already asleep, and even Carter was nodding. The incredible exertions of the day had caught up with them. They couldn’t have stayed awake at that moment even if they’d wanted to.

Home sweet home, thought Ben, as St Peter’s chimed eleven o’clock.

Mr. Wachowski looked down on Ben affectionately as he slept.

The old man shuffled around the room, quietly checking on his sleeping guests. He found a moth-eaten blanket and laid it carefully over Ben and Lucy, who were leaning against each other.

“You have a nice long rest, Ben Kingdom,” Mr. Wachowski muttered. Then he left the room as quietly as he was able, pausing only to lock the door behind him. Regardless of the rain that was rattling down from the sky, regardless of the curfew, Mr. Wachowski walked along the corridor to the front door and stepped out into the night.

“This is my lucky day,” he chuckled.