Chapter 21

Cassie and Siân followed the railway tunnel down. The walls changed from black brick to the softer, squishier red-brown, shot through with blue light. They walked past the spot where they had first met Twm, through the opening into the wide central corridor.

Cassie clutched the carrier bag of treats, squeezing the handles tight. The corridor was empty. High, high above them the blue veins of light interlaced like streams of rain flowing over glass. The dark doorways that led who-knows-where in the warren were eyeless sockets looking back at her. The scrawls of black shapes, people, animals, houses, plants, were a dark riot on the walls.

Where would Twm be?

They couldn’t just wander down here aimlessly. It was huge.

As if Siân had read Cassie’s mind, she said, ‘We should go down towards Fiedown, where the tylwyth teg sleep.’

‘What if Gwen’s there?’ Cassie twisted the bag, letting the plastic dig into her wrist.

‘Then we make sure she doesn’t see us.’

Before they headed off, Cassie checked to see that the drawing of Penyfro Mountain was still beside their entrance way. It was. She touched her fingertips to it gratefully.

Then, they headed on. They could hear their own footsteps, no matter how softly they tried to walk. Cassie wished she could quiet the thumping of her heart.

‘What was that?’ Siân stopped. Looked up. They both listened. Was it a faint cry? Had someone called out? Or was the darkness playing tricks on them? Cassie held Siân’s frightened stare, the whites of her eyes clear to see. The shout, if there had been one, didn’t come again. They kept walking.

Hie!

The cry was closer this time. Accompanied by footsteps. Someone, something, running towards them? Or away? The echo made it impossible to locate.

‘Down!’ Siân whispered. They both dropped to the ground, as far into the shadow of the wall as they could. Cassie had found a dark hoodie to go with her leggings. Hopefully they were like two small stones, barely there in the blackness.

She risked a peek. Two tylwyth teg, neither of them Twm, ran from one of the openings, glanced about quickly then plunged into a different side passage. The lead boy yelled again at the girl who ran behind.

They hadn’t spotted Cassie and Siân, curled up small.

‘This might not be such a good idea,’ Cassie said.

‘It’s the best one we’ve got.’ Siân helped her to her feet.

They kept to the wall, ready to drop and curl up like woodlice if the tylwyth teg came back. Perhaps it was their ears getting more attuned to the sounds, or perhaps it was fear raising phantoms, but it seemed that there were sounds of life coming from all directions now – distant shouts, stones kicked by scurrying feet, even, once, the certain sound of breathing coming from somewhere way too close for comfort.

Cassie forced her feet to keep moving. For Byron, for Mam and Dad, she had to do this.

They reached the main crossroads. The place where the sides of the corridor gave way to two enormous arches; on one side, the Tanglement, with its strange piles of objects, a museum to the world above; on the other the Thorn Hall. It was the hall that drew Cassie. In the blue light the bare branches of the enormous, gnarled tree threw prying finger-shadows on the ground. The air smelled dry and dusty, though the skeletal leaves strewn about suggested it might once have been lush with growth.

Cassie entered the hall.

‘Where are you going?’ Siân asked.

‘I just want a quick look.’

‘But what about—’

‘I’ll be quick.’ She wanted to touch the tree. Although it looked old, and ill, tired under the weight of itself, there was something gentle about it. Like an old dog who just wanted to lie out on a sunny porch, or a grandparent settling down in a comfy armchair. She could almost hear its sigh. Nain’s nain thought blackthorn trees were used in evil spells by witches. But the book in the library had said that they were a mixture of good and evil – the way most people were, she supposed. It felt like a person, somehow, a tired person who’d seen and done enough.

Cassie stepped under the branches, right up to the enormous trunk. The bark was patterned with deep ridges, years and years of growth. She rested her palms flat, and, for a moment, Annwn wasn’t quite so scary, it might be the home of a monster, but it wasn’t only monsters here.

‘You cannot keep following me everywhere I go.’ The voice came from above. She looked up. There was Twm, curled up in the crook of one of the lower branches, looking as cool as anything.

‘We found you!’ Cassie said, delighted.

‘You shouldn’t be looking,’ Twm snapped. He lowered himself down, hanging from the branch with both hands before dropping, with bent knees, to the floor.

‘We’ve brought you something,’ Siân said, ‘but it’s not a gift. And it never belonged to us.’

‘It’s a bribe,’ Cassie added.

‘A trade,’ Siân corrected.

‘What trade?’ Twm was interested, it was clear. His head tipped to one side and the crotchety look of a few moments before was gone.

Siân took the carrier bag from Cassie and held it out, handles spread open, revealing the feast inside.

Twm dropped his head to look, gave an excited growl, and reached for the box of fake Jaffa Cakes.

Cassie reached out to cover the bag with her palm. ‘Not so fast. It’s a trade, which means you have to give us something. Siân, tell him.’

Twm’s eyes narrowed as he glared at the bag and the rowan bracelet on her wrist, Cassie saw the unmistakable flash of blue as a current of magic shot through him.

‘I’ve been reading all about you,’ Siân said. ‘In all the legends you lot seem to really like treats. Cakes and fresh milk and sweet porridge, stuff like that?’

Twm gave a shrug that might have been yes and might have been no.

‘We’ll give you everything in the bag if you can tell us what Byron gave to Gwen and how we can get it back.’

Twm barked a short laugh. ‘I can’t tell you that.’

‘How about if I add this?’ Siân put the carrier bag down and swung her backpack around. She pulled out Taid’s book and held it so he could see the cover: the prow of a ship cutting through waves, a golden eye painted on the wood, glaring at its destination. ‘It’s all about the Trojan War.’

His fingers reached out for the book, his face, for a moment, didn’t look like the face of a half-wild tylwyth teg, it was the face of a curious little boy. Then he snatched his fingers back. ‘What use is that to me? I can’t read it.’

Siân opened the cover, ‘It’s illustrated.’

Twm’s eyes widened as he saw the gods, the monsters, the heroes within. It was clear that he was hungry for the book, that he yearned for it more than for all the chocolate treats squished together. For the first time, Cassie wondered what the stories meant to him. Why was he so interested, when he had magic of his own, and the glimmers and wonders that Gwen could conjure?

‘Give it to me,’ Twm said.

‘Tell us what Byron gave first,’ Siân replied.

Twm squirmed on the spot. Then he threw up his hands. ‘Zounds! I can’t tell you because I don’t know, all right? I can’t remember. I can’t even remember if I ever knew. I forget so much, all the time.’ Twm’s face furrowed into a deep sadness, a sadness that was at once of the moment and at the same time long, long held. Twm’s sadness sat close to the surface. He shook his head. ‘I can’t tell you, none of the Helynt can.’

So, there it was. If the only people who knew were Gwen and Byron, and neither of them were telling, then there was no hope. Cassie felt as sad as Twm looked.

‘Well,’ Siân said suddenly, ‘what can you tell us?’

‘What do you mean?’

‘I don’t know. Why does she even want Byron? What’s she going to do with him? Will he be turned into a boar and hunted by his own dogs? Not that he has any dogs. But that’s the sort of thing you do, isn’t it? What did she do with Alun Wyn? Did he die? How did he die? Do you know any of that?’

Siân lifted the carrier bag and swung it gently by the handles. Was Twm tempted?

‘I’ll tell you what I know,’ he said. He snatched the bag in a flash, and the book too. He hugged them close for a second, his eyes closed as the hard cover pressed against his chest. Then, he was all business. ‘Sit,’ he said.

Cassie dropped to the floor. The soft ground had been made by leaves upon leaves upon leaves slowly falling and flaking. Under the arching branches, on the comfortable earth, Cassie almost forgot, for a moment, that they were in danger. Twm opened the book reverently. His fingers traced the words, but it was the illustrations that had him rapt, from the green-haired sorceress with the golden apple on the first page, to the wooden horse and fall of the city at the end, he was enchanted. Siân tore open the Jaffa Cakes and ate one before passing them to Twm.

As he bit, and chewed the orangey jammy chocolate, he looked at the pages open on his lap.

‘So,’ Siân prompted. ‘What can you tell us? What does Gwen want with Byron?’