“Finish the torch,” Beowulf tells him.

“Could be it had babies.”

“Finish the torch,” Beowulf says again, and he reaches for the golden horn of Hrothgar, still dangling from a loop on his belt. “You can keep the wee dragons busy while I take care of the she-troll.”

“I’ll make a lovely morsel,” snorts Wiglaf, tying the damp wool securely about one end of the branch. Soon, with a few sparks from his flint, the bough has become a roaring torch. “The water burns,” he says, and forces a smile, passing the brand to Beowulf.

“I will see you again, my friend Wiglaf, and soon,” Beowulf tells him, then, before Wiglaf can reply, Beowulf wades into the pool and disappears through the opening in the tangle of roots. Briefly, the hollow place beneath the trees glows yellow-orange with the torch’s light. When the entrance has grown dark again, Wiglaf moves farther away from the tarn, climbing back up the bank to sit out of the wind among the oaks. He lays his sword across his lap and watches the water and the things moving about just beneath it, and tries to remember the end of the story of Hildeburh and the Frisian king.

The passage below the trees is narrow, and Beowulf stands near the entrance for a time, the cold water from the tarn flowing slowly about his knees. The ceiling of the tunnel is high enough that he does not have to stoop or worry about striking his head. He holds the brand in his left hand, Hrunting in his right, and the torchlight causes the walls of the cave to glitter and gleam brilliantly. Never before has he seen stone quite like this, neither granite nor limestone, something the color of slate, yet pocked with clusters of quartz crystals, and where the roots of the trees have pushed through from above, they have been covered over the countless centuries with a glossy coating of dripstone, entombed though they might yet be alive.

Don’t tarry here, he thinks. Do this thing quick as you can, and be done with it. And so Beowulf follows the glittering tunnel deeper into the hillside, and when he has gone only a hundred or so steps, it opens out into a great chamber or cavern. Here the water spilling in from the tarn has formed an underground lake. He can only guess at its dimensions, as the torchlight is insufficient to penetrate very far into that gloom there below the earth. But he thinks it must be very wide, and he tries not to consider what creatures might lurk within its secret depths. The waters are black and still, and rimmed all about with elaborate stalactite and stalagmite formations.

The teeth of the dragon, thinks Beowulf, but he pushes the unpleasant thought aside. They are only stone, and he has seen the likes of them before. He takes a few steps into the cavern, playing the torchlight out across the pool, when suddenly it gutters and goes out, as though it has been snuffed by a breath both unseen and unfelt. The blackness rushes in about him, and it’s little consolation that a lesser man might now retreat and relight the torch.

The oil from the tarn has burned out, he tells himself. It was no more than that. I am alone in the dark, but it is only the dark of any cave.

But then, suddenly, an eldritch glow comes to take the place of the extinguished torch, a bright chartreuse light like the shine of a thousand fireflies sparking all at once. And Beowulf realizes that this new illumination is coming from Hrothgar’s golden horn, hanging on his belt. He reaches for it cautiously, for surely anything that shines with such radiance must be hot to the touch. But the metal is as cool as ever. Cold, in fact. He tosses the useless torch aside and unhooks the horn from his belt. There is nothing healthy in this new light, nothing natural, though he cannot deny it holds a fascination and that there is some unnerving beauty about it.

“So the demon shuns the light of the world,” he says, speaking only half to himself, captivated by the horn’s unearthly splendor. “But it also knows I cannot find my way down to it without some lamp to guide me, so I am given this, a ghostly beacon fit only for dwarves, that I may arrive and yet not offend her eyes.”

For a moment, he stares out across the lake, seeing nothing, hearing nothing but the steady drip of water from the cavern’s roof and the indistinct babble of the stream from the tunnel flowing gently about his legs into the pool.

“Show yourself, aeglaeca!” he shouts, expecting if not her answer at least the company of his own echo. But there comes neither. Only the sounds of water, which seem to make the silence that much more absolute.

“This is not like you!” Beowulf shouts, much louder than before. “You were bold enough when you stole into Heorot to murder sleeping men! Have you now lost your nerve, she-troll?” But once again there is no reply and no echo.

“Then I shall come down to you!” he bellows as loudly as he can. And Beowulf begins to undress, for his iron breastplate and mail are heavy and would surely drag him straight to the muddy bottom of the subterranean lake. “We will meet in whatever dank place you now cower,” he cries out across the water, “if that is how you would have it!”

Does she hear me? Is she listening? Is she crouched out there somewhere, biding her time, laughing at me?

Beowulf leaves his armor and belt, his tunic and breeches and boots, bundled together and lying in a dry place at the edge of the pool. Carrying only Hrunting and the golden horn, which is glowing even more brightly than before, he wades out into the icy water. The floor of the lake is slimy underneath his bare feet, and once or twice he slips, almost losing his balance. When the water has risen as high as his chest, Beowulf draws as deep a breath as he may and slips below the surface. Holding the horn out before him like a lantern, he swims along the bottom. The pool is stained with peat from the tarn and by silt, and the glow of Hrothgar’s horn reaches only a few feet into the red-brown murk. But soon he can see the bottom, strewn with the bones of men and many sorts of animals jumbled together—horses and wild boars, deer and auroch, the toothsome skulls of great bears and the wide, pronged antlers of bull moose. Her dining hall, then, this lake below the hill, and for long ages must she have returned to this place with her victims, feeding where none will disturb her.

Nestled in among the bones are gigantic white crayfish, their spiny shells gone as pale as milk down here in the eternal night, and they wave their huge pincers menacingly as Beowulf passes. There are other things, as well, eels as white as the crayfish and large as sharks, their long jaws armed with row upon row of needle-sharp teeth. Whenever they come too near, he fends them off with Unferth’s sword. Only once does the blade find its mark, carving a long gash in a serpentine body and sending the eel slithering away to safety. Blood clouds the water, making it still harder for Beowulf to find his way.

He rises for another gulp of air, only to discover that this far out the ceiling of the cave has grown unexpectedly low, now mere inches above the pool. He can see that it slopes down to meet the water only a few feet ahead, so this will be his last breath unless he chooses to turn back.

“If the Norns decree I should survive this ordeal,” he says, wiping water from his eyes, “then by the gods, I will teach you to swim, Wiglaf.” And then he takes another breath and submerges again.

Below him, the grisly carpet of bones has thinned out, and Beowulf soon comes upon an immense cleft in the lake’s floor, a wide black chasm beckoning him on to still-greater and more terrible depths. A weak but persistent current flowing into the hole tugs at him, and he hesitates only a moment, sensing this must surely be the path that will lead him to Grendel’s mother. There is no knowing how far it might extend, if it will ever come to another pocket of air, but he pushes on, regardless.