The first rule we make is not to look at the sky.

‘Or, you know, anything, if you can help it,’ Phil says. ‘Do as little looking as possible.’

The second rule was that we had to march in single file, one hand on the shoulder of the person in front, after the first time one of us was lured off the path by something in the depths of the forest and nearly lost for good.

We’d been following Holly through the forest – ‘Are you sure it’s this way, Holly?’ / ‘Yes, I’m sure, why do you have to question me all the time, Pearl?’ – for what might have been ten minutes or ten hours when we realised Julian was missing. After what might have been ten minutes or ten hours but in fact turned out to be about forty-five minutes, we found him back in the clearing where we’d begun, gorging himself on berries.

‘I never thought I’d taste these again,’ he said, when we asked him why he’d wandered off. ‘I’m so hungry. God, I’m so hungry.’ There are reddish-purple stains all over his mouth and hands.

I remember the taste of the berries as they forced them down Finn’s throat, dark, rich, ripe, bursting with an indescribable sweetness.

I bite my lip hard enough to draw blood and suck on it like a vampire, trying to keep the taste of them out of my mouth.

The third rule we make is that we have to be tied together at all times.

It’s Phil’s idea, when we end up back in the clearing again another hour later, after Cardy suddenly broke ranks and sprinted into the trees, yelling that he could see lights, he could hear voices, and it was Rhymer, he knew it was, he was close, and he needed us!

‘I wanted to bring rope, but I didn’t have any lying around, so this will have to do,’ Phil says, pulling a ball of red wool out of her bag.

We loop it through belt loops and backpack straps, binding ourselves in a line, Holly at the front, me at the back, Cardy, Julian and Phil in the middle. ‘This way, if one of us gets distracted, the rest of us can pull them back,’ Phil says.

It seems like a pretty good system – especially since we immediately have to put it into practice by yanking Julian away from the berry vines.

But it’s not flawless.

‘Do you hear that?’ I say, as we attempt our third march into the forest.

I stop dead, but because I’m on the end of the line, I’m promptly dragged off my feet. That sends Phil, who’s in front of me, toppling as well, and we all go down like a row of dominos.

If there are fairies watching us from the trees, they’re probably laughing their arses off, but that’s the least of the thoughts in my mind.

‘Help me,’ Finn moans in the distance. ‘Help me. Please.’

‘It’s Finn!’ I say, scrambling to my feet and immediately falling over again.

‘No, it’s not,’ Phil says. ‘It’s a trick.’

‘No, she’s right!’ Holly says. ‘Can’t you hear him?’

‘Help …’ Finn groans again.

‘Oh no,’ Julian moans. ‘Go away go away go away go away!’

‘Rhymer?’ Cardy calls. ‘Rhymer, is that you?’

‘Oh my God,’ Phil breathes. ‘Mum! Mum!’

We tear off into the forest, tripping each other over as we try to race into different directions, until the wool bindings snap.

We all end up back in exactly the same place.

The trunks of the trees are a silvery ring around the clearing. They cast long shadows in the morning sun, the silhouette of outstretched branches like reaching fingers. The breeze ruffles the leaves, and I’m not sure if I’m imagining it, but it sounds like they’re laughing.

Phil slaps Julian’s hands away from the berries and then looks at his watch. ‘It’s half-past seven,’ she says.

‘Four hours,’ Cardy says. ‘We’ve been here for four hours and we haven’t got anywhere.’

‘We can’t give up now,’ I say. ‘I have an idea.’

My idea is not the most elegant idea anyone has ever had, especially since we don’t exactly have the right equipment. Add ‘convenient pharmacies’ to the list of things fairyland should consider instituting, along with a decent education system.

Maybe fairies are wrong, and maybe three isn’t a magical number. Maybe it’s four. Because the fourth rule we make is the rule that works.

It takes us four hours, but when we march into the forest again, hands on each other’s shoulders, bound together with red wool, our ears stuffed full of wads of fabric torn from the bottom of Cardy’s shirt, we make it to the other side.