The door of the polar bear room: slammed.

Basti’s gone. Disappeared. And that’s one door that won’t be opening anytime soon. We slump with our backs against the front door. It’s hopeless. He’ll never come out. So much for four half-made Christmas hats or anything else.

‘I don’t want to go to an orphanage, Kick,’ Scruff cries. ‘I hate gruel. And they’ll never let me put sugar in it.’

I look at him. All of them. Right. Up to me to mend this.

Open our door. Dinda’s just disappearing, her door’s closing –

‘Wait!’ I shout, running out, three Caddys behind me. The door slams, as if she’s completely given up on the Reptilarium and its impossible knot of a family.

‘I can help,’ I say loudly, right outside her house.

The door stays resolutely shut.

‘I know exactly what to do. To fix everything.’

Still shut. One last chance. ‘Dinda, we know why Basti never speaks to you. I want to help. I know how.’

The door opens. A sliver of a crack. Dinda’s eyes are red from crying.

‘I can make this work,’ I plead.

‘Please, Princess Dindi.’ Pin holds up his hands in prayer.

A hint of a smile.

‘We’re going to fix this,’ I say, firm. ‘Whatever it takes. Because we have to. Because it was our fault.’

‘Whatever it takes,’ Scruff repeats, looking doubtfully at me.

‘So, Miss Desert Rose, what do you propose?’

I lick my lips. Glance around at the other houses in the square. ‘We have to hide the Reptilarium among all the others. Just like that refuge was hidden once. We have to put candles all through it whether Basti likes it or not.’ A deep breath. ‘And the big task: we have to tidy it up.’ Another deep breath. ‘And then convince him to have a Christmas.’

‘A few trifles,’ Dinda laughs in hopelessness. ‘Anything else?’

‘Yes. We have to make him be friends with you.’

‘Right. All that, in a day.’

I nod firm. ‘Yep. My dad says you never get anything done unless you give it a try. So just do it.’

Dinda looks dubiously at the Reptilarium then dubiously at us.

‘Caddys to the rescue!’ Bert throws up her arms.

It’s my sign. ‘Troops, action stations!’ I command before Dinda can talk any of us out of it. ‘Girl hero, you ready?’

‘Aye aye, captain.’

‘Boy heroes?’

‘Aye aye, captain!’

Swiftly before me, in a line, are three perfect salutes. I look our reluctant neighbour straight in the eye and wink. ‘We can do it, Dinda. And do you know why? Because we’re from the bush!’

Two minutes later. Four kids from the desert plus one very glamorous photographer standing on a snowy footpath of London’s Campden Hill Square, staring up at a magical but decidedly neglected building called the Kensington Reptilarium. With a plan to transform it. In a single day. On Christmas Eve. Are we mad? Yes. Barely a month ago, who would have thought that any of them would be doing this?

‘Oh my, it’s a task.’ Dinda’s shaking her head with the sheer, crushing hopelessness of it. ‘We’d need a frightfully large amount of people. And we only have today . . .’

‘Actually, we only have four hours, until it gets dark,’ Scruff says, looking at his watch. ‘That’s about three p.m., isn’t it? This being London and all.’

‘Steady on, mister,’ Dinda smiles, then sighs. ‘But it’s today of all days. With the last-minute shopping to do, trees to finish off, presents to wrap. Who’s got the time? Anyone?’

I look at her. I look at all of them. ‘Excuse me, but where’s our spirit of the Blitz, troops? You Brits won the war on it, Dinda. Well, we just need to see it. Here. Now. Again. It’s legendary. Give me half an hour. I’ll get them out. You told us that Basti was really respected in this square. That lots of the older people still remember him fondly. The little boy who climbed trees, the rescuer of his mates, the war hero, actually, despite what he thinks. He can’t be taken away now, he can’t be locked up. We have to save him.’

And off I set, just like that, striding away determined to the nearest house.

Rap loudly.

A gentleman answers. He’s in the throes of gluing paper chains together, a huge string is wrapped around his neck. I explain. His face softens. ‘Sebastian Caddy? Why of course. My father used to play with him all the time. Spoke of him extremely fondly.’ He unwraps himself from the chains. ‘What do you want me to do?’

Bert catches it all. Heads off to another house. Scruff strides away with Pin. Each with one goal: to save Basti, save the Reptilarium, before dark.

Because we’re from the bush. And we’re Dad’s kids. And we get things done, we make them right.

Half an hour later. Campden Hill Square. A huge group of people heading out their doors into the glittery cold of Christmas Eve – it’s just stopped snowing, the world’s twinkly and white. Every one of them cluttered up with buckets and ladders and brooms and brushes; old people, young people, tall women, short men, dogs and children and people who’ve never before met.

Heading to? The Kensington Reptilarium, of course.

And over the next couple of hours, in what little daylight London’s got left, everyone works, and works, and works. Everyone in the square, on December the 24th, summoning that renowned spirit of the Blitz. To save the man inside the shabbiest house in their midst. The one who they’ve all heard about or remember. The man who saved four mates once – and sent a candle back to this very square from the Western Front. Aged just fifteen years. And then returned to the thick of battle. Once again, for his mates.

And was punished most savagely for it.

‘Come on, Basti,’ I plead at the polar bear door. ‘Come out, have a look.’

‘No!’ comes the muffled cry. ‘Leave me alone.’

‘I’ll give you half my Cadbury’s ration chocolate,’ Scruff entreats. ‘It’s one of my all-time favourites . . . and yours. And it’s not given away lightly. As you well know.’

‘No.’

A pause. ‘I’ll give you the whole lot. This is some sacrifice here.’

‘No.’

‘Basti! Basti! Cuddle?’ Pin begs.

Hesitation. Then, ‘No,’ quiet, from the other side.

‘Please, Basti,’ Pin persists, ‘I love you.’

Silence.

Then the captain does something none of us hear very much: he cries a wail of complete abandonment. I look at Scruff, at Bert, my heart breaking. Because it sounds like Pin’s weeping not just for Basti but for Dad too. He’s well and truly gone, we know that, he’s never coming back and it’s hit Pin at last and it’s all, finally, pouring out. Our little brother gets it. Finally. He’s growing up.

Look.

The polar bear door, opening a sliver.

A velvet cap peeking out – the one Bert’s been trying to get her hands on the entire time we’ve been in this place. Two bushy eyebrows. Two most concerned eyes. The hat leans down, right at Pin-level, and jiggles.

Jiggles again, most enticingly.

Pin giggles despite himself and gently lifts the cap off its rightful head and places it triumphantly on his own – then thinks better of it and places it on Bert’s.

‘Yes?’ I ask.

‘Yes,’ Basti sighs. ‘Resistance is futile. You lot, you lot.’

‘Yippeeeee!’ we all exclaim.

‘Come on, the window.’ Scruff’s now pulling both his uncle’s arms.

‘Twenty seconds and that’s it.’

Oh no. The Caddy kids are having none of that. We march our uncle to a window and keep him there, trapped. As luck would have it we’ve got Dinda right outside, on a tall ladder, looking most un-Dinda-like in a checked apron and high heels (leopard print) and a matching handkerchief around her head. She’s briskly scrubbing a pane of glass next to an extremely dashing man from down the road. He shakes each of our hands.

‘Captain McAuliffe – Ian to you and me. Delighted to be of your aquaintance. Delighted indeed!’

He’s feverishly painting the window frames. Has just returned from the war himself. When he sees Basti his eyes light up and he gives the older man the most respectful, most heartfelt salute.

Basti’s eyes widen. He steps back in shock. ‘But I’m a terrible embarrassment . . . aren’t I?’ He looks at me in bewilderment. ‘None of them want me here.’

‘Actually,’ I say, ‘they couldn’t think of anything more horrible than you being taken away from this Square. On Christmas Eve, of all nights. You’re a big part of it, Basti. You’re a legend. A hero. Just like a lot of other people around here. And you know what? They want to help.’

Scruff flings up the window and shouts to all the neighbours swarming over the house. ‘You’re doing this for Basti Caddy, aren’t you? He needs to hear it with his own ears!’

‘Yes!’ they cry out, ‘yes!’

‘Basti, welcome back, old man.’

‘Jolly good show!’

‘We expect a tree to be climbed before tonight.’

‘Just trust us, mister.’ Dinda smiles the most beautiful smile, right at him, the ghost of a fifteen year old in it from long, long ago. ‘Just trust us, you, for once.’

‘Three cheers for Mr Caddy!’ Captain McAuliffe yells.

And Uncle Basti?

Well, let’s just say that at this very moment, with the cheering all around him, it looks like he could almost burst into light.

With happiness.