When they got home, Bianca’s dad suggested she get into bed and rest. ‘You’ve got school tomorrow, Bianca . . .’

‘School? I can’t go to school. I need to help Finn,’ Bianca said angrily, and the concerned expression on her dad’s face intensified. ‘Didn’t you see what was happening back there, in the hall? That man in the top hat stopped me from explaining about the silver book, and he’s not really a man at all! He’s four children on each other’s shoulders. I saw them go into an old book factory last night and one of them has hands like giant snowflakes and . . .’

‘I’m sorry, Little Bee,’ her dad said, using a pet name he hadn’t for years. ‘I think your mother and I have been so worried about Finn we’ve failed to think about how all of this is affecting you. Perhaps it would be a good idea for you to go and visit your granny.’

‘No!’ Bianca’s insides lurched.

‘You love visiting her, and you’d even get to miss a bit of school. Think of it like a little holiday, just until we’ve worked out how to help Finn.’

‘I want to help Finn too. I promised him.’

‘What’s happened to Finn has upset you deeply. I can see that.’ Dad put an arm round her, hugging her head to his chest. ‘It’s only natural for you to use your wonderful imagination to try and make sense of all this.’ His voice was kind, but Bianca wanted to cry. ‘You don’t really think that magic books are freezing children, and that an adult with a top hat is really four children who live in a factory – do you?’

Bianca was unsure how to reply. If she said yes, Dad would send her away and she wouldn’t be able to help Finn, but she refused to pretend she’d made it up. ‘I don’t want to go to Granny’s. I want to be near Finn, and you and Mum.’

‘I’ll discuss it with your mother tonight.’

‘You have to believe me,’ Bianca said, trying again. ‘Tonight, at midnight, Gwen Olsen will be found frozen in the park. I think there will be two other children there too, but I don’t know who they’ll be . . .’

‘Shhh now, my Little Bee. You’re upsetting yourself. You need to sleep.’ He placated her as if she were four years old, taking her upstairs, removing her shoes, helping her put on her nightie and pulling the covers up to tuck her in.

Bianca wanted to shout at him to believe her, but knew it wouldn’t help. She didn’t want to hurt his feelings. He was already so sad. Once in bed, she turned towards the wall and closed her eyes, pretending to go to sleep.

It was down to her to stop Jack, Quilo, Pitter and Patter. No one was going to help her. No one believed her. As she lay there with her eyes closed, her father watching her from the end of her bed, Bianca formulated a plan.

When Bianca woke up it was dark. Her father was gone from her room. Picking up her alarm clock, she saw it was 4.30 in the morning. She slipped out of bed and got dressed as swiftly and silently as she could. She found her school uniform and hid it inside her duvet cover, then wrote a note to her parents saying that she’d got up early and gone to school. She propped it up on her desk. Pulling on her boots and coat, Bianca checked she had her gloves and diary, and then crept along the landing to her brother’s room.

She had laid Sposh on the pillow where Finn had left him. Bianca untied the red scarf from round the rabbit’s neck, retying it round her own wrist as a good-luck charm. She needed luck for what she was about to do.

Taking one stair at a time, she reached the front door making the minimum of sound. She didn’t hear anyone stirring. Reaching up to the coat rack, she grabbed her woolly beret and a scarf, putting them on before she opened the front door.

Stepping out into the street felt like entering a magical world. The sky was black, but the ground, the shrubs and the cars had grown a fur coat of frost, tinted yellow by streetlights. The pavement was buttered with a thick glassy smear of ice. After Bianca’s feet had gone from under her several times, she gave up walking and slid along as if she were ice skating. She knew exactly where she was heading. Only one place held the answers to her questions. Downy Falls.

There wasn’t a car on the road, or a person in sight. As she crossed the bridge over the canal, entering the industrial district, she felt a further drop in temperature.

When the bookbinding factory appeared in the distance, the tumbledown building was lit from inside by a turquoise light.

In the time it had taken her to walk there, the sky had warmed from black to the colour of an aubergine’s skin.

Taking a steadying breath, Bianca crept along the street, bent double, and ran swiftly through the gateless entry posts of Downy Falls. Ignoring the path to the door, she scouted around the perimeter of the building. Under a row of windows, she found a stony flowerbed. In it was a wizened shrub, devoid of sap and life, and an equally dead lilac tree. Wriggling until she was in the nook between the dead plants and the factory wall, she settled into her hiding place, hoping that none of the strange children would venture round this side of the building.

Kneeling up, Bianca peeped through the window into the factory. She had a blurry and imperfect view. The glass reminded her of a frozen stream she had

once seen. The bubbling water had been transformed into a glassy solid, circles of air trapped beneath its surface.

The factory appeared to be abandoned. She couldn’t see anyone inside. She listened but heard no movement. Summoning her courage, she rose a little higher and cupped her hands around her eyes to see better.

Through the window she saw a cavernous room with a concrete floor. The otherworldly turquoise light seemed to radiate from a big machine that wound through the space like a snake, its tongue a black conveyor belt. The machine looked old. Some parts were spotted with rust, some looked broken and others appeared to be new and made of silver. At the back, Bianca could make out a staircase up to a walkway that led to three doors. She wondered if the children lived here, if the rooms were bedrooms, or just offices.

Sinking back into her hiding place, Bianca considered how long it might be before the children arrived, or woke up, and went about their business. She sat, watching the aubergine sky lightening slowly by degrees. She hoped her parents had found her note, although, she realized, when she didn’t turn up to school, they’d get a phone call. She didn’t want them to think she’d been frozen, although once Dad learned that Gwen was in the park, she hoped he would realize what she’d told him was true, and understand why she’d left the house before he got up. Her investigation was important.

There was a sudden blaze of white light inside the factory and Bianca risked a quick peep in through the window. The middle door on the raised walkway was open. The light coming from inside the room was blinding.

Pitter and Patter danced out, running to the iron staircase, tapping their feet as they ran down two steps and hopped up one. Quilo followed, standing at the top of the stairs with his hands on his hips, waiting for them to finish their routine. Then he beamed as if an idea had struck him, and, turning, he jumped backwards onto the railing and slid down the banister past the tap-dancing pair as Jack emerged and closed the door, shutting off the bright light.

Not wishing to be seen, Bianca ducked, blinking to adjust her eyes.

‘Do we have the books?’ Bianca heard Jack ask, and she immediately popped back up, hoping to see a silver book.

‘I have two . . .’ replied Pitter, pointing at a grey bag slung across his chest.

‘. . . I have two too!’ Patter added, pointing at her bag.

‘Why must I always be the stomach?’ Quilo grumbled, holding out the long black coat to Jack.

‘You are the lungs,’ Jack corrected him, pulling the dark glasses from a pocket and putting them on.

‘We don’t complain about being the legs . . .’ Patter said.

‘. . . even though your farts stink like bad eggs,’ Patter added, and they both hooted with laughter.

Quilo harrumphed, turning his back on the twins, standing with his feet astride, waiting for Jack to put his arms into the long black coat. Once dressed, Jack leapfrogged neatly onto Quilo’s shoulders.

Pitter and Patter stood side by side, an arm locked around each other’s shoulders, and bent their legs. Quilo took hold of both their outstretched arms and walked up their legs with Jack on his shoulders. Bianca marvelled at their acrobatics, thinking that Quilo must be very strong unless Jack weighed next to nothing. Quilo sat down on their linked shoulders, between Pitter and Patter’s heads.

Jack smiled, fastening the coat around them, and the creepy man-sized figure lolloped forward.

‘Now remember,’ Jack said. ‘We are to keep watch for that girl, Bianca Albedo. She nearly ruined everything at the meeting yesterday.’

‘She’s trouble,’ Patter’s muffled voice said.

‘Danger doubled,’ Pitter agreed.

‘Oh, poo!’ Quilo huffed, and the belly of the coat ballooned. ‘She ran away as soon as you looked at her.’

‘The bond of love the humans share is hazardous to our plan,’ Jack said. ‘It is powerful and triggers memories. Whatever happens, we cannot let Bianca Albedo get her hands on one of our special books.’

‘Then we’ll stay away from the library.’ Quilo’s voice came from inside the coat. ‘She knows about that place.’

‘Oh, I have a much better place to give out our books than the library.’ Jack smiled. ‘This morning we’re going to distribute our beautiful presents to the keen children who arrive first at the school gates.’

And with that the towering figure lurched out of the factory.