Goldpaw pressed on through the shimmering tunnel until it opened out and a large turquoise lagoon sparkled before them. Trees surrounded the water, their branches lined with flickering candles and dripping with wax, and Fox wondered whether these were the trees that spelt out prophecies to the Unmappers.

There was a bridge, made of vines, that led over the lagoon to a beautiful temple fronted by a flight of paint-splashed steps and guarded on either side by what looked like two stone unicorns. A waterfall rumbled into the night on the far side of the lagoon and beside that was an enormous tree with windows of all shapes and sizes, large pipes leading out into the waterfall itself and a sign above the door carved into its trunk which read: The Bustling Giant.

‘Doodler’s Haven,’ Goldpaw told them. ‘This lagoon was once the busiest place in the kingdom. It was where we made the ink for the rain scrolls. Dashers would return from the jungle with satchels crammed full of thunderberries and they would be mixed with marvels – droplets of rain in its purest form collected in Rumblestar and carried here by dragons – by Dunkers to make ink. Finally, the ink would rush through those pipes into the waterfall and down into this lagoon. Then Doodlers would scoop it up into jars and use it to paint the rain scrolls on the steps leading up to the temple.’

Goldpaw smiled sadly. ‘I wish you could have seen a rain scroll on a Doodler’s easel. The hidden magic behind your rain. They were paintings so majestic they made you gasp in wonder.’

‘Paintings can be that powerful?’ Fibber murmured, more to himself than to anyone else.

Goldpaw nodded. ‘The rain scrolls are carried with the sun scrolls from Crackledawn and the snow scrolls from Silvercrag into your world every sunrise by our dragons so that you have your weather.’ She paused. ‘Or at least they were before Morg came to Jungledrop.’

Fox glanced at Fibber. He was listening to the panther with a look of awe on his face. The hardness that had been buried inside him had begun to thaw, as Fox had noticed, and although it still came out now and again (when he was scared or worried or when Fox wound him up because a lifetime of regarding someone as a rival is hard to shake), Fibber had been softening nonetheless. And this was because he had a secret.

It had all begun when his teacher, Mrs Scribble, noticed something in him last term that everybody else had missed. And, when a child who has been overlooked by their parents and almost everyone else in the world is finally noticed, they often turn out to be a very different person. Prior to his sessions with Mrs Scribble, Fibber would have scoffed at Goldpaw’s words, but, in discovering Fibber’s hidden talent and nurturing it, Mrs Scribble had also taught him to look at the world in a different way. And gradually Fibber’s tongue had become less sharp and his heart less thorny. But then he had heard about the Forever Fern on the train and seen the determination in his sister’s face and a familiar panic had set in. If Fox presented his parents with an immortalising fern, which was guaranteed to make millions, he’d be the one sent away. So, just like his sister, Fibber had concluded that finding it was the only option open to him.

And yet now, as he stood before a place like Doodler’s Haven in the presence of a mighty Lofty Husk, he was overwhelmed by wonder. Suddenly he realised that the quest for the Forever Fern was about something far bigger than beating Fox and impressing his parents. It was about saving Jungledrop and the Faraway and all the people who lived there. And somewhere, deep down, he thought that perhaps it was about saving a sibling, too – about trying to patch up a relationship that, until now, Fibber had pretty much given up on. Maybe this was a chance to work with his sister, as Goldpaw had told them, rather than against her, and to come out the other end as friends rather than rivals.

Fox, meanwhile, was experiencing no such revelations. She was simply feeling impatient with the Lofty Husk. ‘I’ve never seen any of these magical rain scrolls back home, or a sun or snow scroll for that matter,’ she said curtly. ‘Talking isn’t going to make the Forever Fern appear. I need weapons and a map.’ Her tummy rumbled. ‘And dinner.’

She huffed. Being a businesswoman with a proper plan in place was proving exhausting work and she would have to remind herself to eat more on this quest. Her lunch back in the Neverwrinkle Hotel seemed a long time ago.

Fox thought of her parents again and the look on their faces when she came bounding back to the hotel with an immortalising fern that would save the family fortune! She tried to imagine the scene. Perhaps a little podium would be nice for when she announced her news. And maybe there could be an orchestra playing some sort of triumphant music in the background – Fox figured musicians were probably quite easy to hire when you were a billionaire-in-the-making. And then there would be the way her parents treated her. Maybe they’d hold her hand when walking down the street or offer to read her a story before bedtime or even remember her birthday. Fox’s heart swelled at the possibilities.

But Goldpaw’s voice, which was level and strong and said nothing at all about dinner, brought Fox back to reality with a bump. ‘You have never seen a rain scroll because magic does not bang a gong when it arrives. It comes secretly and silently, without fuss or pomp. Dragons leave the scrolls in the overlooked parts of your world – deep inside caves, tucked into mountain crags, high up in trees – and within moments they vanish and you are none the wiser, though you have the weather your world needs to survive.’

The Lofty Husk strode over to a nearby tree, stopped before it, then opened her mouth. Fox flinched at the rows of bone-bright teeth, but the panther simply breathed upon the bark and golden dust poured from her mouth.

A satchel appeared at the foot of the tree. Fox blinked. Had it been there all along, camouflaged, or had the Lofty Husk conjured it out of thin air?

‘The greatest explorers in this kingdom have tried to find the Forever Fern – and failed,’ Goldpaw said. ‘I tried and so did the other three Lofty Husks. But we failed, too. Then the prophecy told us that only those from far-off shores can unearth the fern’s whereabouts and your arrival here leads me to believe that it is speaking of you two. But you will only survive if you listen to me.’

The panther sat back on her hind legs, her large tail curled round her, and looked the twins square in the eye. ‘Don’t get lost, don’t get tricked and be careful what you eat.’

She breathed more golden dust that fell about the twins, making Fox sneeze, before it vanished completely. ‘That breath will protect you from the sun’s glare and from the sticklebugs’ bites,’ Goldpaw said. ‘The objects inside this satchel will help with everything else.’

Fox eyed the crumpled leather bag. ‘Why is there only one satchel? There are two of us.’

‘As I said before,’ Goldpaw replied, ‘you must work together.’

Fox threw Fibber a filthy look and snatched up the satchel. She unbuckled it and shook out the contents: a blank piece of parchment, a small mirror and – most disappointing of all – a spoon.

‘You’re sending us off into the jungle armed with a SPOON?!’ she cried.

Beside her, Fibber was looking increasingly worried. ‘What about spears and stuff? And maps?’

‘The parchment is a map,’ Goldpaw answered. ‘An indescribably rare one called a flickertug map. It is impossible for Lofty Husks or Unmappers to cross from kingdom to kingdom, but the rulers of Jungledrop, Rumblestar, Crackledawn and Silvercrag can communicate with one another through enchanted mirror rings and I have it on good authority from my peers that this flickertug map is, in fact, the last of its kind in all the Unmapped Kingdoms.’

Fox picked the map up and then jumped as a strange silver glitter shimmered across the surface of the parchment. But no places or words appeared.

‘You have to tell the flickertug map where you want to go,’ Goldpaw said. ‘It would not yield the whereabouts of Morg’s stronghold or the Forever Fern when asked, but that might simply be because the wrong people have been asking…’

Fox felt an unexpected shiver of excitement fizz through her.

‘And the mirror?’ Fibber asked, turning it over in his hands. ‘What’s that for?’

‘The jungle is full of tricksters,’ Goldpaw replied. ‘Its magical creatures, animals and plants survive because they are masters of disguise: they can hide in exposed places; they can dissolve before your eyes; they can disappear without trace. But, with a doubleskin mirror, you can compete. Just hold the mirror up to your surroundings and your skin, hair and clothes will adopt the exact colours and patterns of your setting: your ear might resemble a leaf, your nose a twig, your tunic the trunk of a tree. Remember, though, that the doubleskin’s magic only lasts a few minutes and you can only use it once before its powers vanish altogether – so you must make it count.’

Fox eyed the mirror mistrustfully. ‘I’ll believe it when I see it.’

‘And, finally, the fablespoon,’ Goldpaw said. ‘Hold it above a plant and the details of that plant will flash up inside the head of the spoon: its name, its character and whether it is food or poison.’ She paused and looked at Fox. ‘But it only works if you say please. Keep these items safe and—’

The panther’s ears swivelled back towards the tunnel. She stood up quickly, her fur on end.

Fibber spun round. ‘What – what’s happening?’

Footsteps sounded in the tunnel and then out rushed an Unmapper – a man this time, with a leaf-tousled beard, raindrop tattoos on his ears and fear plastered across his face. ‘It’s Iggy,’ he panted. ‘He’s gone!’

‘Gone?’ Goldpaw growled. ‘I sent him home and watched him leave for Timbernook.’

The Unmapper shook his head. ‘He never arrived. His parents are scouring Timbernook as we speak, but –’ he looked down – ‘there are monkey tracks near his house. They don’t look like the tracks the silvermonkeys leave. These ones are bigger, and spiked where claws might be. And they lead north. Towards the Bonelands…’

Goldpaw paced back and forth by the edge of the lagoon. ‘We always feared that Morg would, eventually, turn her attention to Unmappers, hoping to steal more magic from them than she can from thunderberries and animals. And now it seems that terrible day has come. Oh, poor Iggy! The terror he must be feeling. And it was on my watch. But for Morg’s Midnights to have broken through the phoenix magic into the heart of the jungle –’ she shook her head – ‘that means the harpy’s power is reaching its height. She will be on the move from the Bonelands soon, so it is not weeks we have left before Jungledrop falls but days!’

For a second, Fox felt a surge of guilt. It was because of her and Fibber that Iggy had been late making his way home. But then she remembered that feeling sorry for people was a sign of weakness and she fought hard to bury her feelings.

The Unmapper took a step closer to Goldpaw. ‘Deepglint is in the Bonelands, you said; he’ll find Iggy and bring him home. Won’t he?’

Goldpaw hung her head. ‘There has been no word from Deepglint for a month now.’

The Unmapper’s face paled.

‘But that does not mean that he is lost to us,’ Goldpaw added hastily. ‘Deepglint might have found Morg’s stronghold and be making plans to seize it. It could be too risky to make contact.’

It was the first time that Fox had detected fear, and unease, in the Lofty Husk’s voice and it made her shuffle a little closer to her brother.

‘I’ll send word via the fireflies to Spark in the Elderwood and ask him to patrol Fool’s Leap. We must get Iggy back before Morg’s Midnights cross over that ravine into the Bonelands.’

Goldpaw turned to the twins. ‘I will stay here and conjure the strongest spells I know to make the boundary safe for the Unmappers again. You should leave immediately. If Morg’s power is nearing its peak, she may be very close to finding the fern. You must find it before she does and plant the pearl so Morg will never be able to harm Jungledrop again. If she swallows that pearl and takes the fern’s immortality for herself, the Faraway will die and so will the Unmapped Kingdoms as we know them. Then Morg will steal all the Unmapped magic and create a new world with the power of the elements on her side.’

‘Yes, yes, all very tragic,’ Fox replied. ‘Now, where will I find shoes and a change of clothes for this quest? My blazer is in quite a state.’

Goldpaw shook her head in disbelief, but it was clear that she didn’t have time to discipline rude children. ‘You will find shoes, clothes and flasks of fresh water in the Bustling Giant.’ She bounded off towards the tunnel with the Unmapper hot on her heels. ‘Now, go!’ she called over her shoulder. ‘There is not a moment to lose!’

The twins made their way round the lagoon towards the Bustling Giant and, once inside the great hollowed hallway of the tree, which was lit by dozens of raindrop-shaped lanterns, they got changed into the clothes hanging up on the hooks there. Fibber put on a pair of patchwork-leaf shorts and a feather waistcoat. Fox chose a short feather tunic, but kept her tie because it made her feel more strategic and businesslike. (It was a strange look, especially when coupled with the moccasin boots the twins found.) They glanced briefly into a few of the rooms leading off from the hallway which were filled with vast cauldrons, twisting pipes and staircases that wound higher and higher up the tree, then they grabbed two flasks of water and made their way outside again.

Fox laid the flickertug map down beside the lagoon and knelt before it. The waterfall roared on, the parchment glimmered silver beneath the candletrees and even Fibber, whose gaze had kept wandering to the temple in the middle of the lagoon earlier, watched the map eagerly.

‘Where is the Forever Fern?’ Fox whispered to the parchment.

At first nothing happened. The map simply carried on glistening in the night.

‘I knew we shouldn’t have bothered listening to that crackpot panther,’ Fox muttered.

She wondered whether the time was coming for her to see if the phoenix tear could somehow lead her to the fern. But then the map’s magic flickered into life and silver words curled out onto the parchment:

Seek the Constant Whinge

Fibber frowned. ‘Who or what is the Constant Whinge? What kind of map doesn’t even show locations!’

Fox gave the map a short, sharp jab with her finger in case showing it who was boss prompted more information. But no new words, or indeed places, appeared. It was only when Fox lifted the map up again that she realised the flickertug’s magic wasn’t finished with them yet.

‘Argh!’ she cried as she stumbled forward. ‘The map’s alive! It’s – it’s dragging me along!’

Fibber shook his head in disbelief. ‘Flickertug,’ he murmured, running a hand over the parchment. ‘Maybe the map will tug us in the right direction!’

Instinctively, Fibber reached out to grab the map. Years of trying to keep one step ahead of his sister were hard to shake, even though he knew that none of that mattered any more. Fox grabbed back and Fibber took a deep breath. He thought of Goldpaw’s words about working with his sister and reluctantly let Fox yank the map away from him.

‘I’ll lead the way,’ she snapped. And, with that, she hefted the satchel onto her shoulder with her spare arm and allowed herself to be pulled towards the waterfall spilling into the lagoon.

Fibber followed close behind, still clutching his briefcase.

‘Do you really want to cart that briefcase through the jungle with you?’ Fox called over her shoulder.

Fibber glanced at the Doodlers’ temple again and Fox followed his gaze. What was it about the building that intrigued her brother so much?

‘The briefcase is coming with me whether you like it or not,’ Fibber panted. ‘I’ve spent too long working on what’s inside to abandon it altogether.’

Fox didn’t have time to remain curious because the map was pulling her through a gap between the rock face and the thundering water. Then she and Fibber were both running behind the waterfall itself, the sound of it pounding in their ears.

Fox had expected it to be dark behind the waterfall, but there was a strange glow coming from the shelf of rock above them that the water careered off. Fox squinted. Hundreds of tiny bats were clinging to it. She had seen bats before – black ones with jagged wings and grating screeches that tore out of cathedral ruins – but these ones were bright white, like light bulbs, and they hung silently, watchfully, from the rock above the twins as the flickertug map led them on.

The sight was so utterly magical that, for the briefest of moments, Fox and Fibber exchanged glances full of wonder. And in that moment, the competition was forgotten because here they were, being led through the light of a thousand luminous bats by an enchanted map, a map that had not even shown the most legendary explorers or the rulers of this kingdom the location of the Forever Fern.

Fox felt an unexpected thrill at the thought of the map choosing her, and being unique – special, chosen – was enough to make her forget, just for a second, that she was unworthy of being loved.

The twins scampered out from behind the waterfall into the knotted undergrowth to find a yellow parrot perched on a low-hanging branch in front of them. They knew, at once, that this was Heckle because the bird took one look at Fibber’s briefcase and started muttering about handbags.

‘Scoot!’ Fibber hissed at the parrot. ‘This is an important mission.’

But Heckle stayed exactly where she was, her yellow feathers lit up by the glow-in-the-dark plants beneath.

Fox glowered at the bird. Seeing her brought back thoughts of Iggy and a prickle of guilt, which she quickly tried to squash. ‘Clear off, Heckle!’ she barked.

Heckle fixed the twins with beady eyes. ‘The girl and the boy are feeling ever so slightly guilty about my beloved Iggy going missing.’

‘Shut it, feather-mouth,’ Fox snarled.

Heckle squawked indignantly, but the flickertug map, it appeared, didn’t have time for conversations because it hauled Fox on again, past an orange plant with clam-like petals that sprang open as Fox brushed past them, then spat out a cluster of spotted frogs that had been sleeping inside. Fibber hastened after Fox and Heckle followed.

Fox threw a glance over her shoulder. ‘That parrot is not coming on this quest.’

Fibber nodded. ‘I’d rather face Morg than spend any more time with that bird.’

But Heckle – who harboured a wild hope that the twins might find Iggy as well as the Forever Fern – had decided that she very much was going with them.