The old man takes the saddle from Beowulf and stands staring indecisively back at Unferth and the two Geats. “Have you seen the tracks?” he asks. “They are everywhere this morning. I do not doubt the spoor would be easy enough to follow back across the moors.”

“There is the forest,” Unferth says, “and bogs, and many stony places where we might lose the trail.”

“Are you Beowulf?” asks Agnarr. “The one who took the monster Grendel’s arm?”

“One and the same,” replies Beowulf. “But it seems I did not finish the job I came here to do. Tell me what you know, and I may yet put an end to this terror.”

Agnarr stares at the Geat a very long while, his hesitancy plain to see, but at last he takes a deep breath and then begins to speak.

“It is an ancient terror,” the old man sighs, then saddles the mare. “In my day, I have glimpsed them from afar, the pair of them, if indeed they be what troubles the King’s hall. They might be trolls, I have supposed, or they might be something that has no proper name. The one you fought, Grendel, and another, which looked almost like a woman. It moved like a woman moves. It had breasts—”

“We know what they are,” says Unferth impatiently, and he glances toward the stable doors. “We would have you tell us where we might find them.”

“As I have said, I cannot say for certain that it was she who visited Heorot last night and did this murder. I only know what I have seen.”

“Where?” asks Beowulf a second time, more brusquely than before.

“I am coming to that,” replies Agnarr, and he ties a heavy cloth sack onto the saddle, looping it through an iron ring. “I just wanted to be clear what I know and what I do not know.”

The old man pauses, stroking his horse’s mane, then continues. “These two you ask after,” he says, “they do not live together, I think. Not many leagues from here, east, then north toward the coast, and past the forest, there is a tarn. Deep, it is. So deep that no man has ever sounded its bottom. But you will know it by three gnarled trees—three oaks—that grow above it, clustered upon an overhanging bank, their roots intertwined.” The old man tangles his fingers tightly together to demonstrate.

“A tarn beneath three oak trees,” says Beowulf.

“Aye, and the roots of those trees, they all but hide the entrance to a grotto. The tarn flows into that fell hole in the earth. I could not tell you where it reemerges, if indeed it ever does. For all I know, it flows to the sea or all the way down to Niflheim. And another thing, I have heard it told that at night something strange happens here. They say the water burns.”

“The water burns,” says Wiglaf skeptically. “And what is that supposed to mean?”

“It is only what I have heard told,” replies Agnarr, shaking his head. He frowns and glares at Wiglaf. “I have not ever seen that fire for myself, nor have I any wish to do so. This is a foul place of which you have me speak. Such tales I have heard, and the things I’ve seen with my own eyes. Once, I stalked a hart across the bog, a mighty stag,” and the old man holds his hands above his head, fingers out in imitation of the rack of a stag’s antlers.

“Three of my arrows in him, three, and yet still he led me from the forest and right out into the marches. With my hounds, I tracked him as far as the tarn and those oaks. It was winter, you see, and we had great need of the meat, or I never would have followed him to that place. The hart, it might have escaped me then. It had only to plunge into those waters, where I could not follow it across to the other side. But it dared not. It knew about that place, whatever dwells there. Rather than face the tarn, it turned back toward my dogs and me and so found its death.”

“You spin a good yarn, uplander,” mutters Unferth, and he gives the man two pieces of gold. “Perhaps you should have sought your fortune as a scop instead of a farmer.”

“Do not mock me.” Agnarr frowns and pockets the gold. “You ask, so I tell you what I know. Seek you the merewife if you dare, if you think her your killer, seek her in her hall below the tarn. Perhaps she’ll even come out, to meet you,” and the man points at Beowulf. “The foreign hero who slew her son.”

“You have told us what we need to know,” says Unferth. “Now be on about your way.”

“So I shall, my good lord,” replies Agnarr. “But you take care, Geat. That one, Grendel’s dam, the merewife, they say her son was never more than her pale shadow.” And then he goes back to loading bags onto his saddle, and his piebald horse whinnies and shuffles about in its narrow stall.

“He’s mad as a drunken crow,” mutters Wiglaf, as the three men leave the stables, leading their own ponies out into the dim winter sunlight. “And you’re mad as well, Beowulf, if you still mean to go through with this.”

“You will never tire of reminding me of that, will you?” says Beowulf.

“Nay,” replies Wiglaf, forcing a smile. “The painfully obvious amuses me no end.”

“The tarn the old man spoke of,” says Unferth, mounting his pony. “I think I know this place.”

“You’ve seen it?” ask Beowulf.

“No, but I have heard stories. Since I was a child. I have heard there is a lake, somewhere on the far side of the wood, which was once known as Weormgræf, the dragon’s tomb.”

“I hope we’re not off hunting a dragon now,” says Wiglaf, gripping the saddlebow and pulling himself up. “I should have thought an ordinary sea troll was nuisance enough for one day.”

“There is a story,” continues Wiglaf. “It is said that Hrothgar’s grandfather, Beow, was plagued by a fyrweorm, and that he tracked it to a bottomless lake across the moors, where he wounded it mortally with a golden spear. The dying dragon sank into the lake, which steamed and bubbled from its flames, and was never seen again. The story says that the waters still burn at night, poisoned by the fyrweorm’s blood.”

Beowulf is still leading his pony by the reins. They are not far from the gates and guardhouse now. “You think Agnarr’s tarn is Weormgræf?” he asks Unferth.

“Fire on water,” replies Unferth, and shrugs. “You think perhaps that’s a coincidence? Or maybe these lands are fair teeming with combustible tarns?”

“We shall see for ourselves soon enough,” says Beowulf, and before long they are outside the gates of Heorot and riding swiftly across the moors toward a dark and distant line of trees.

It is late day by the time the three riders at last find their way out of the shadow of the old forest beyond the moorlands and begin searching for some way across the bog. A low mist lies over everything, and the air here stinks of marsh gas and pungent herbs and the stagnant, brackish water. The ponies, which gave them no trouble either on the moors or beneath those ominous trees, have become skittish and timid, flaring their nostrils and shying away from many of the pools.

There are flocks of crows here, and Beowulf wonders if they are perhaps the merewife’s spies. She might have other spies, as well, he thinks, for there must surely be some vile magic about her. No doubt she may command lesser beasts to do her bidding. The crows circle overhead and caw loudly, or they watch from the limbs and stumps of blighted trees that have sunk in the mire.

“It is hopeless,” despairs Wiglaf. “We will not find a way across, not on horseback. The ground here is too soft.”

“What ground,” says Beowulf, looking out across the marches. “There is hardly a solid hillock to be seen. I fear you are right, Wiglaf. From here we will have to continue on foot.”

“I am not so great a swimmer as you,” Wiglaf reminds him. “I’m no sort of swimmer at all.”

“Don’t worry. I will not let you drown,” says Beowulf, who then turns to Unferth. “Someone should stay behind with the horses. There are wolves about, and bears, too. I’ve seen their tracks.”