There are no attacks during the night-an encouraging omen. We depart with the rising of the sun, bidding short farewells to relatives and friends. I want to look back at the huts and walls of the rath as we leave-I might never see them again-but that would be inviting bad luck, so I keep my eyes on the path ahead.

It's a cloudy day, lots of showers, the coolness of autumn. Summer's been late fading this year, but I can tell by sniffing the air that it's finally passed for certain. That could be interpreted as a bad sign-the dying of a season on the day we leave-but I choose to overlook it.

We march east at a steady pace, staying close to Sionan's river. Our boats were destroyed in a demon attack some months back, so we can't cross the river here. We have to go east, cross where it's narrow, then make our way west from there.

The earth is solid underfoot and there are plenty of paths through the trees, so we make good time. Ronan and Lorcan are to the fore of the pack. I'm next, with Orna and Run Fast.

He's eager to move ahead of the rest of us but we hold him back-otherwise he might disappear in the undergrowth like a rabbit. Connla and Fiachna are behind us. Connla's sulking and hasn't said a word since we left. Goll brings up the rear.

I brood upon my reasons for leaving the rath as we march, feeling uneasier the more I think about it. Mostly I chose to leave because of the vision of my mother. But there was another reason-fear. The rath seemed to grow smaller every day. I felt so confined, I sometimes found it hard to breathe. I had nightmares where I was trapped, the wall of the fort closing in, ever tighter, squeezing me to death. If our worst fears come true and we fall to the hordes of demons, I don't want to die caged in.

Is it possible I created the vision to give myself an excuse to leave? I don't think so. I'm almost certain it was genuine. But the mind can play tricks. What if this is folly, if I'm running away from my fears into worse danger than I would have faced if I'd stayed?

If it wasn't a trick-if the vision was real-why would the ghost of my mother send me on this deadly quest? She wouldn't have urged me to risk my life if it wasn't important. Maybe she wants to help me unravel the secrets of my past. I've always longed to know more about my mother, where I came from, who my people were. Perhaps Run Fast can help me find the truth.

If that's just wishful thinking, and my past is to remain a secret, maybe our rath is destined to fall. My mother's spirit might have foreseen the destruction of the MacConn and acted to spare me.

Whatever way I look at it, I realise I left for purely selfish reasons. The MacConn need me. I shouldn't have abandoned them because I was afraid, to hunt down my original people or save myself from an oncoming disaster. I should go back. Fight with them. Use my magic to protect the clan as best I can.

But what if there's some other reason my mother appeared, if I can somehow help the MacConn by coming on this crazy trek? Banba said we should always follow the guidance of spirits, although we had to be wary, because sometimes they could try to trick us.

Ana help me! So many possibilities-my head is hurting, thinking about them. I should stop and give my brain a rest. Besides, there's no point worrying now. We're more than half a day's march from the rath. We couldn't return to safety before nightfall. There's no going back.

Everybody was quiet during the morning's march, thinking about those we left behind and what lies ahead. We stopped to rest and eat at midday. Ronan and Lorcan caught a couple of rabbits, which we ate raw, along with some berries. After that, as we walked slower on our full stomachs, the talk began, low and leisurely, with Fiachna asking Orna a question about the three-bladed knives she favours.

There were lots more questions for Orna after that. Those from our rath know all there is to know about each other. Orna and Run Fast are the only mysteries in the group, and since Run Fast simply grins and looks away when you ask him anything, that leaves Orna as the focus for our curiosity.

She's had four husbands, children by three of them. She says she likes men but has never been able to put up with one for more than a couple of years. Goll laughs at that and says the pair of them should marry, since he won't live much more than a few years.

"I wouldn't have a lot to leave except memories," he grins. "But they'd be good memories. I had three wives when I was young and didn't disappoint any of them!"

"Except when you lost your eye and kingship," Connla smirks, sending Goll into a foul mood.

"You shouldn't provoke him like that," Fiachna whispers harshly.

"He's an old wreck," Connla retorts. "My father's a king and I plan to follow in his footsteps. I'll speak to the old goat any way I like."

"We're not in the rath now," Fiachna says. "We're a small, isolated group and we need to rely on each other. Think on-Goll might hold your life in his hands one night soon."

As Connla scowls and considers that, I ask Orna about her children. Were they among those who arrived yesterday?

"No," Orna says shortly, gaze set straight, her shaved head glistening in the rain. There are tattoos on both her cheeks-the marks of Nuada, the goddess of war-dark red swirls which suck in the gaze of all who look at them in an almost mesmerising way. "They're dead. Killed by demons a week ago."

"Ana protect them," I mutter automatically.

"Ana keep them dead," Orna replies tonelessly.

"You didn't burn the bodies?"

"We couldn't find them. Demons slipped in through our souterrain and made off with them. They must have been playing in the tunnel. I told them a hundred times never to go down there. But children don't listen."

Her eyes are filled with a mixture of sadness and rage. As a warrior, she won't have allowed herself to mourn. But women can't make themselves as detached as men. Our hearts are bigger. We feel loss in a way men don't. Orna has the body and mind of a warrior but her heart is like mine, and I know inside she's weeping.

Ronan and Lorcan spar with Orna in the evening as we cross bogland. She knows a few knife feints which are new to the brothers and they practise until they've perfected them. Ronan and Lorcan, in turn, know lots of moves which Orna doesn't and they teach her a few, promising to reveal more over the coming days.

Once warriors were secretive. They kept their techniques to themselves, always wary of their neighbours, knowing that today's friend can be tomorrow's enemy. The Fomorii changed that. Now we share because we have to-warriors, smiths, magicians. The demons have united the various tuatha of this land in a way no king ever has. A shame we can't join forces and face them on a single battlefield, in fair combat-I'm sure we'd win. But although demons aren't as clever as humans, they're sly. They spread out, taking control of paths and routes, limiting the opportunities to travel, dividing prospective allies. We share our arms, learning and experience with others where possible, but I fear we shan't be able to share enough.

As Ronan and Lorcan spar with Orna, Connla asks Fiachna for advice. He has an idea for a new spear, topped with several sharp fins, and wants Fiachna's opinion. Fiachna listens politely, then explains why the weapon won't work. Connla's disappointed but Fiachna cheers him up by saying if there's a smith in Run Fast's village who can make weapons like the boy's knife, perhaps the two of them can come up with something along the lines of Connla's design.

I chat to Run Fast, asking him again for his real name, where he's from, if he has family. But he doesn't answer. After a while Goll nudges up beside us. "Having trouble, Little One?" he asks.

"He won't tell me anything," I huff. "I'm sure he could-if he can tell us his people need help, he must be able to tell us his name-but he won't!"

"The heads of the touched are hard to fathom," Goll says, rustling Run Fast's hair. "My second wife had a brother like this. He couldn't dress himself, wield a weapon or cook a meal. But he could play the pipes beautifully. In all other ways he was helpless-but set him loose on the pipes and he could play any man into the ground."

"What happened to him?" I ask.

Goll shrugs. "He went wandering one day and ate poisoned berries."

"Berries!" Run Fast shouts, rubbing his stomach. He picks up on certain words every so often and repeats them.

"It's not that long since we last ate," I tell him. "Wait until dinner."

"Berries," Run Fast says again, sadly this time. Then he stamps his right foot several times and looks at me hopefully. "Run fast?"

"No," I groan. "Not now. You have to stay with us."

"Run fast," he sighs, stamping the ground one last time, letting me know that he could race up a storm if I gave him the go-ahead.

Goll laughs. "He's a lively one. You'll have your hands full looking after him!"

"I might just push him into Sionan's river when we cross," I huff.

"We wouldn't be able to find his village then," Goll says.

"I'm not sure we'll find it anyway," I grumble. "How do we know he's leading us the right way? He could have come from a southern tuatha for all we know."

Goll squints at me with his good eye. "You're in dark spirits, Little One. Are you tired?"

"No."

Goll tickles me under the chin until I laugh. "Tired?" he asks again.

"Aye," I sigh. "I'm not used to all this walking. And you go so quickly! I've only got short legs."

"You should have said."

"I didn't want to look like a... a..."

"A child?" Goll smiles. "But you are. And a tiny wee bee of a child at that."

"Just because I'm small doesn't mean I can't keep up!" I fume, quickening my pace. But I've not taken five or six steps when Goll wraps a burly arm around my waist and hauls me off the ground. "Hoi!" I cry. "Put me down!"

"Stop struggling," Goll says and settles me on his shoulders, my legs either side of his head. "We might have need of you later. You're no good to us fit for nothing but sleep."

"I'm fit to turn you into a frog if you don't put me down!" I grunt, but secretly I'm delighted and after struggling playfully for a minute, I settle back and let Goll be my horse for the rest of the afternoon, admiring the view from up high and saving my strength in case I'm called upon to fight demons in the dark.

We come to the crossing point of Sionan's river late in the evening. The river's narrow here, easy to ford. This is the joining point of two tuatha. A large cashel once stood here, the largest in the province. A couple of wooden roads lead up to and away from the place where the impressive stone fort stood. Many carts used to travel this way and the roads were carefully tended. But the cashel's a pile of rubble now and the roads are in disrepair. We'd heard the cashel had been overrun by demons but hoped the reports were wrong. This would have been the ideal place to shelter tonight.

"What now?" Connla asks, studying the untidy mound which was once the pride of the province. "Cross the river or camp here?"

"Cross," Ronan and Lorcan say together.

"There's no safety here," Ronan says.

"Where demons attack once, they'll attack again," Lorcan agrees.

"And many can't cross flowing water," Ronan says. "We'd be safer on the other side."

Connla nods but looks uneasy. There was never a fort on the opposite side of the river, just some huts where folk of the neighbouring tuath dwelt. They used to greet those who crossed the river and either grant them the freedom of their tuath or turn them back. The huts are still standing but we can't see any people. They might be hiding or they might all be murdered, demons sheltering inside the huts from the sun.

"Come on," Goll says, setting me down and taking the lead. "The sun's setting. Let's get across and find a hole for the night which we can defend."

There are dugouts tethered to the banks of the river, bobbing up and down. Each holds four people at most. We head for the nearest pair. Ronan and Lorcan team up with Run Fast and me. Goll, Orna, Fiachna and Connla take the other. Lorcan grabs the rope of our dugout and hauls it in. He's almost pulled the boat up on dry land when I get a warning flash.

"Lorcan! No!" I scream.

He reacts instantly, drops the rope and leaps backwards just in time. A huge demonic eel unleashes itself at him, rising out of the boat like an arrow shot from a bow. Its jaws are impossibly wide, filled with teeth which would be more suited to a bear.

The demon snaps for Lorcan's head and only misses by a finger's breadth. It lands hard on the earth and writhes angrily, going for Lorcan's legs. Ronan steps up beside his brother and stabs at the place where the demon's eyes should be. But it doesn't have any. It's blind, operating by some other form of sense.

Orna jumps on to the demon's back and hacks at it with her three-bladed knives, one in either hand. The demon bucks and twists desperately, trying to dislodge her, but she rides it like a pony, digging her heels in, face twisted as she screams hatefully, tattoos rippling with fury.

Connla takes aim and hurls a spear at the beast, down its maw of a mouth. The spear sticks deep in its throat. The demon chokes and slams its head downwards, trying to spit out the spear.

Goll darts forward, grabs the shaft of the spear and drives it further into the Fomorii's throat, twisting savagely. The demon spasms, then weakens. Suddenly the warriors are all over it, hacking away like ants trying to bring down a badger. Fiachna, Run Fast and I watch from nearby.

"Do you think I should help?" Fiachna asks, fingers tapping the head of an axe which hangs from his belt.

"They're in control," I tell him.

And, moments later, the battle's over and the eel demon lies at their feet, covered in the grey blood which previously pumped through its veins, torn to pieces, jaws stretched wide in a final death snarl.

Goll grasps the handle of the spear, yanks it out and hands it to Connla. He laughs and claps the younger warrior on the back. "A master throw!"

Connla smiles sheepishly. "I didn't mean to hurl it down the beast's throat," he says with untypical modesty. "I aimed for the top of its head. But it moved. I got lucky."

"I'll always take luck over skill," Goll says, clapping Connla's back again. The pair grin at each other like lifelong friends.

"I've never fought a water demon before," Orna grunts, wiping her knives clean on the grass. She dabs at the final few drops of grey blood with her middle finger, then rubs it into the centre spots of her spiral tattoos, one after the other.

"They're rare," Ronan says, studying the demon, turning it over on to its back with his foot. "We're lucky it's not night or it would have been stronger."

"Come on," I mutter, glancing around uneasily. "It'll be sunset soon. More will be coming."

That silences everyone. After a quick check to make sure the second dugout is free of demons, we're in the boats and crossing the river as swiftly as possible, everybody keeping one eye on the water, wary of attack from beneath.