Peering around the corner of the building, Bianca felt a fizz of panic as she watched the tall, dark figure tottering down the road. What should she do? Should she race ahead of them and warn the parents at the school gates? The disbelieving faces from last night’s meeting filled her mind. No. It wouldn’t work. They thought she was mad with grief, and she was meant to be going to school herself.

Bianca couldn’t stop the strange children from giving out their books, but she could get evidence about what they were doing and take it to the police. Then people would have to listen.

She thought about the things Jack and the others had said. It frightened her that they knew her name, but she took strength from the fact that they thought she was dangerous. They had said she was trouble, that she could ruin their plan, which made her all the more determined to do so.

The sun had risen. The day was lighter, though it barely felt any warmer. After waiting for a minute, to make sure the strange children weren’t going to come back, Bianca ran to the factory door and tried the handle.

It was locked. She was going to have to break in. Rushing back to the window, she pressed her nose to the glass, double-checking that the coast was clear. When she pulled back, the skin of her nose had briefly stuck to the cold glass. Taking off her glove she touched the window. ‘It’s not glass!’ Bianca exclaimed. ‘It’s ice!’

Taking a large flint from the flowerbed, she smashed at the ice until she’d made a hole big enough to climb through.

Dropping onto the factory floor, Bianca shivered. The inside of Downy Falls felt like a refrigerator. Looking around, she saw colourful graffiti tags and patterns decorating the mottled concrete walls. One or two adventurous plants had sprouted through the floor, their stems now bowing, weighed down by crystals of ice. She cautiously approached the machine that took up most of the floor. To her it seemed like a sleeping sea serpent that might, at any second, wake up and devour her.

She peered into the mouth from which the conveyor belt extended like a black tongue, but there was no sign of any silver books. She carefully examined each section of the machine, but found no clue about the books it made. She looked around. You couldn’t make a book out of nothing. Where was the paper? Where was the ink?

A tiny white flake drifted past her eyes, and Bianca looked up, startled to see that a portion of the factory roof was missing, only skeletal iron beams remaining. Beyond them the thick low clouds were finally unloading their cargo of snow.

‘Oh!’ Bianca reached up and caught a flake on her gloved hand, then stuck out her tongue and caught another, feeling it turn to water. She couldn’t remember the last time it had snowed before Christmas. There had been snow three years ago, in February, but it hadn’t settled. Most of the time it was too warm for snow, but how Bianca loved the snow when it came. She tilted back her head, feeling the delicate flakes landing on her cheeks and eyelashes like the gentlest of kisses. Her soul lifted and she smiled to see the flakes getting heavier and falling faster. Reaching out her arms, she twirled – and then stopped. What was she doing? Now wasn’t a time for playing! She was here to find evidence, and clues, anything that would break Finn and the others free from the ice that trapped them, and stop more children being frozen. She felt a hot flush of guilt.

She redoubled her search of the factory floor, looking under machinery, in every corner, but found nothing.

The only places she hadn’t yet explored were the rooms at the top of the iron staircase. Bianca felt a thrill of fear as she put her foot on the first step. What was waiting for her behind the three doors at the top? Taking care that each footstep landed as silently as a snowflake, she slowly climbed upwards. Glancing down, she felt a lurch of fear as she saw that the snow

was telling tales on her. Her footprints were all over the factory floor, clearly visible in the fallen snow. She would have to wipe them away when she went back down.

Stepping onto the walkway, Bianca went to the first door and pressed her ear against it. She heard nothing. She tried the handle; it went all the way down. She opened the door a crack, peering in, and found herself looking at

old tools and machine parts. An old dried-out mop and bucket stood in the corner. Everything was covered in cobwebs and the floor was carpeted with dust. It didn’t look as if anyone had been inside this room for years.

Making her way to the second door, she saw an eerie wisp of smoke escaping from underneath it. When she tried the handle, she was surprised to find it was freezing cold. The door wouldn’t open. It was locked. This was the room from which Jack and the others had emerged, backlit by a dazzling blaze of light. She listened, but heard nothing on the other side.

The third door was stiff, but she threw her weight against it as she pulled down the handle, and it popped open to reveal a room stacked with enormous rolls of paper for the bookmaking machine. This room, like the first, looked as if no one had been inside it for a long time.

Returning to the middle door, Bianca was certain that all the evidence she needed was on the other side. Running her fingers around the door frame, she searched for a key, but found none. She put her foot to the frame as she tugged and twisted the handle, but couldn’t open it. She was about to run at the door, and throw her weight against it, when she heard approaching voices.

A crackle of panic in her chest exploded into fizzing fear. There was no time to get down the stairs and out of the window. She ran to the first door and slipped into the storeroom, leaving a thin crack so she could see out. She gasped as she remembered her telltale footprints in the snow. It was too late to do anything about them now.

The factory door opened.

‘Well, that was easy. That was quick.’

‘Jack, you were so dazzlingly slick.’

‘It’s easy to give a book to a schoolchild,’ Jack said, jumping down and taking off the dark glasses to reveal those strange opal-like eyes, ‘when they want it so desperately.’

Quilo did a forward roll off Pitter and Patter’s shoulders, tumbling out of the coat and landing on his feet.

He began slapping his ballooned cheeks and chest in a rhythm, moving his lips into larger and smaller circles to change the pitch of the sound. Wiggling his bottom, he trumpeted a surprisingly high-pitched fart tune.

Pitter and Patter joined in, chuckling with glee as they tapped their feet on the concrete floor in time with Quilo. Starting slowly, they built up a pattern of taps that increased in pace and intricacy as they skipped across the floor. Bianca found her head was bobbing along in time as she marvelled at the speed with which their feet tapped, and inwardly rejoiced as they danced her footprints away.

A row of icicles hung from a railing beside the big machine. Jack flicked them and they rang like a glockenspiel.

‘There’ll be four tonight, and tomorrow five more, ’ Pitter said, framing his face with jazz hands.

‘One more today than ever before!’ Patter declared.

‘If you read, you know a book is a door,’ Pitter sang out.

‘It’s production-line time. Hit the factory floor!’ Patter spun round and pointed at the machine.

Jack finished the impromptu song by dragging their fingers along the icicles, making them sound like a wind chime.

From her hiding place, Bianca had a clear view of the children’s movements around the factory. She took out her diary and pen and sketched them. She wrote JACK below the reedy figure with the ponytail and white suit, QUILO next to the chunky, cherubic boy in a bearskin, PITTER beneath the grey boy, and PATTER beneath the grey girl.

Now that Bianca was still, she was cold. She began shivering, which made it hard to control her pen, and, although she tried to carry on, the shivering became a juddering. Inside her head the rattle of her chattering teeth was terrifyingly loud. She clamped them together and put away her diary.

Had the factory got colder since the children had entered? It certainly felt like it.

She heard a clatter of metal and looked down to see Pitter and Patter laying out fine sheets of metal, flat on a table. Jack opened a pouch attached to their belt and carefully reached a long finger and thumb into it, drawing out something. Placing it on the palm of their free hand, Jack stroked it with the tip of one finger, staring at it with intense focus. Something glittered, but Bianca couldn’t see what it was. Jack carefully laid it on one of the metal sheets, then took out another small object, and another, repeating the action five times.

‘The mirror splinters are on,’ Pitter declared.

‘Now the plates are done,’ Patter said excitedly.

Carefully lifting each of the sheets of metal, they slotted them into the big machine. Jack stood at the top of the printing press, at the opposite end to the conveyor belt, and laid their strange snowflake hands on a silver bar.

Bianca heard a sound like the creaking of old leather or the cracking surface of a frozen lake.

‘Ready?’ Pitter asked.

‘Steady?’ Patter asked.

‘GO!’ boomed Quilo.

There was a high-pitched whine as Jack spooled ice from their fingertips into the machine. It immediately clattered into action, printing the words and pictures from the silver plates onto pages of ice.

Bianca was shuddering violently with the cold now. Her fingers were blue. She pulled on her gloves, hugging her hands under her armpits. She suddenly realized why she’d not been able to find Finn’s book. It had been made from ice! Once he’d read it, it had melted away, which explained the spilt water on the stack of books beside his bed. That’s why there was no evidence of the books ever existing!

‘Each night, more and more children are reading our bedtime story,’ Jack said triumphantly as the first book came out on the conveyor belt.

‘It’s so heart-warming to see,’ said Quilo, and the others seemed to find this very funny.

‘It will please her,’ Pitter said.

‘It will ease her,’ Patter agreed.

‘We will make her strong again,’ Jack proclaimed.

As the fifth book was being printed, Jack released their grip on the machine and watched as it was bound together and delivered by the conveyor belt.

Five glistening silver books lay there in a row. Bianca found herself leaning towards them. She wanted one so badly it hurt.