“ALMOST THERE, GAV,” Jema McShane said, and squinted against the bleak mountain wind. She scanned the horizon before she helped her brother away from the car. “Isn’t this a pretty spot?”

“Oh, aye, lovely,” Gavin McShane said, as he gripped the handles of his rolling walker and glanced at the surroundings. “It’s Baltic out here, you mad quinie.”

Twilight crept up from the horizon as the late fall temperatures in the Scottish Highlands began a rapid plummet. In another hour they’d be courting hypothermia. Jema would have to be careful about how long she kept her brother out in the cold. Under his thick plaid woolens and trench coat, Gavin’s joints and limbs had begun to resemble spindly kindling. His sluggish circulation made him chill easily. In his condition pneumonia was not only possible, it would be lethal. She’d misjudged how much time it would take to get him this far, but at least they were here.

Amyotrophic lateral sclerosis had been eating away at Gavin’s brain and spinal cord for two years now. Because there was no cure for ALS, he wasn’t expected to live far beyond three.

At least helping him along the dirt path from the makeshift parking lot to the Neolithic dig wasn’t the ordeal she’d imagined. The grad students and volunteers working the site had carted out most of the heavy gear when they’d left for the day, packing the soil to a concrete hardness. Tomorrow they’d finish for the season by taking down the huts and collecting the cables and wires that provided power and lighting for the trenches.

How easy it was to ignore the fact that Gavin, who two years back had been a healthy beast of a soldier three times her size, now barely weighed two stones more than she did.

“Reminds me of those tyre graveyards they have in Kuwait,” Gavin said sounding bored. But at least he was looking around them. “Is this what they do with ours now?”

“Not typically. Usually they grind up tyres and pave the roads with them. All of Europe does.”

She tugged gently on his arm to bring him to a halt on top of the plywood. Active excavation units were surrounded with the broad, thin boards, keeping the pit walls from collapsing by dispersing the weight of the excavators. Slowly, she and Gavin turned the walker around so the seat faced the site. As she set the brakes, he all but fell onto the padded cushion. But when he realized she’d been watching him, he sat up straight and took the torch from her. She gave his shoulder a gentle squeeze before she stood aside.

A foot in front of them lay the last open trench at the site, where she had been doggedly trying to find any sign of the burial she felt sure was there. Hundreds of old car and truck tyres surrounded it on three sides, stacked and waiting for tomorrow. In the morning, the pit would be backfilled with soil and draped with tarps, which the tyres would hold down and cushion against heavy snow drifts. Though the smell of the old rubber baking in the sun had made her sick over the summer, now it just made her feel sad.

But she still had tonight, Jema told herself as she took off her backpack, lowered it over the side, and let it drop. She pulled off her down jacket.

“Keep the torch light on me while I climb down,” she said. “You’ll be able to see where I’ve been working.” She eyed the plywood under the walker. “Don’t move any closer to the edge. The soil there is dodgy.”

Gavin watched her tuck her jacket over his legs. “You’re off your head, you know. What if you have a fall? I’m not leaping to your rescue.”

“You can still use a phone, you great hellbeast,” Jema reminded him as she extracted her mobile, checked the signal and then placed it in his lap. “Dial one-oh-one if I keep screaming, or nine-nine-nine if I stop.”

“Maybe I’ll call for a cab.” He glowered at her, which made her feel like she was seeing her reflection in his face. He had the exact same gray-blue eyes she had. “Be careful, Jay.”

Jema grinned and kissed him on the brow. Gavin hadn’t called her by her twin name in ages. “Ever and always, Gee.”

The short ladder extending down into the trench had been hand-painted with a V-9, designating it the ninth trench in which they’d found Viking-Age artifacts. The most exciting, an ax-head still attached to a piece of wood handle, had been tentatively dated back to the first century BCE. Radiocarbon dating on the organics would be done back at the laboratory, but Jema wasn’t interested in the weapon—it’s what it might indicate.

V-9 was a burial pit. Jema would swear to it.

Of course, they hadn’t yet found a grave, or remains, or any indication that a body had ever been buried here. Initially the trench had been filled with roots from several ancient, enormous oak tree stumps they’d found on the surface, which had made excavating it tricky. Jema had read several articles which speculated the Vikings deliberately planted trees over such graves in order to disguise and protect the dead, but she wasn’t sure if she agreed. For one thing the tree stumps had been massive. When the tree ring dates came back, she wouldn’t be surprised if they’d been planted a thousand years before the burial would have taken place.

The moment they had begun digging out the trench, however, Jema had begun feeling the oddest sensations. Her skin became acutely sensitive, while her heartbeat seemed to slow down. Whenever she touched a stone or root her fingers seemed to pulse with some frantic energy. She kept seeing in her mind the crude drawings she had studied depicting Freyja’s Eye, even when she didn’t want to think about them. She knew all of it was unprofessional, possibly delusional, and would get her thrown off the dig if she told anyone about it. So Jema had kept it to herself while she continued digging.

Now she reached the bottom of the trench and stepped off the ladder before waving and calling up to Gavin, “I’m in.”

“You’re daft,” he called back, but kept the light from the torch trained on her. “There’s nothing down there I can see. It’s not but a big hole in the ground.”

“That’s because you’re a soldier, not an archaeologist,” Jema said and pointed to the feature she’d uncovered last week. “This is an inner wall face. The stones used to build it are these slab-like rocks called orthostats. They were stacked in parallel and vertical positions to create slots.”

“Slots?” Gavin said and frowned down at her. “Like a casino?”

“No, like keyholes…or air holes.” She took out a dental tool from her backpack and gently inserted the tip into one of the slots until it almost completely disappeared. “I feel something on the other side of this. It may be a created space, like a burial chamber.”

He leaned forward to peer over the edge. “What, then, you want to unlock a grave?”

“Be careful,” she said and eyed the position of his feet. “Don’t put weight near the lip of the unit or the sidewall might give way.” They’d already removed the stabilizing boards around the base of the pit. “You’ll fall on top of my great discovery.”

“A grave with slots,” he mocked as he sat back.

“Or the final resting place of Freyja’s Eye,” Jema said and moved the probe to test another space. “Can you imagine it? A golden diamond the size of your fist, carved to honor the goddess’s own beautiful eyes. Although it probably isn’t even a diamond. It might be a fist-sized topaz, or a hunk of polished amber.”

“Which can also use sunlight to melt off your face,” Gavin put in. “Don’t forget that part. I’ve not, since you told me.”

“That’s just another myth,” she assured him. “The Vikings always exaggerated their legends to strike fear in the hearts of their enemies. There’s another one that says for every enemy that the Eye kills, it also takes the life of a loved one.”

“So that’s where they got that eye-for-an-eye thing,” Gavin said and rubbed his brow. “I always thought that came from the Bible.”

“No, it’s actually from Hammurabi’s Code,” she told him. “Mesopotamian king of Babylon, and not a particularly forgiving man. You would have liked him.”

Her brother made a rude sound. “Stop showing off how brilliant you are. Why are you so obsessed with this bloody rock? You can’t sell it or keep it.”

Her heart twisted as she shrugged and removed the probe. “The Eye will go to the National Trust, to be worshipped by countless generations of kids forced on museum outings. The find, however, would be mine. A discovery of that magnitude would get me a publication in every archaeological journal in the world. Edinburgh would finally offer me a full-time teaching position.”

Gavin uttered a short laugh. “You hate Edinburgh.”

She did, but that didn’t matter. “I could take a flat for us near the uni, and get a home carer to look after you while I’m at work. You remember the doctor there who is testing that new drug treatment–”

“Jema, I’m going to die, and soon, and it won’t be pleasant.” He stared down past her. “Unless I can make it happen faster, and cleaner.”

He was talking about ending himself, Jema thought, and swallowed a surge of bile. “No, Gavin. That isn’t the way.”

“Why not?” he asked her, a strange intensity in his voice now. “I roll over the edge, fall into your pit, and break my neck. Fast and clean.”

“Unless you don’t break your neck, and end up a quadriplegic with ALS,” Jema retorted. “You’re a barrel of giggles, Gee. Bed-ridden on a respirator, not that much.”

She shook her head and clenched her teeth to keep from saying more. Talk of the end of her twin brother’s life had not been the reason she’d brought him. Somehow she’d thought he’d be as excited about the dig as her. Quickly she turned away from him but as she did her heel caught. Without time to brace her fall, the back of her head bounced off stone slabs in the trench wall. As she landed hard in the corner, the air whooshed from her lungs and dirt landed in her face.

“Jema,” Gavin yelled. “You all right? Answer me.”

She frantically brushed the soil from her eyes to find the light from the torch swinging back and forth over her head. Her lungs ached but she managed to draw in a long breath before she coughed.

“Jema, I’m calling for help!”

“No,” she gasped and cleared her throat. “No!”

She pushed herself up, the dental tool pushing painfully into her palm. She gripped it as she struggled to her knees then clambered to her feet.

“I’m fine,” she called up to her brother, and silently winced as she touched the back of her head. She squinted into the torch light. “Don’t call anyone. Oh, damn, damn, damn.”

“Are you hurt?” her brother demanded.

She held up her other hand to shield her eyes. “Yes,” she hissed, her fingers probing the tender spot on the back of her head. At least she didn’t feel any blood.

“What’s that in your hand?” Gavin asked.

“It’s my…” She’d been about to say ‘probe’, but the glitter of gold stopped her. Instead of her tool she was staring at a dirt-crusted, golden torque set with orange gems. “What the… Where did…” She glanced down at where she had fallen. “Gee, aim the torch down there!”

Delicate silver links pocked the dirt, and ended in a large disc sticking up from the ground. Both took on a silvery glow as sparkling light came from some roots sticking out of the wall she’d hit.

Jema reached a shaking hand for the disc.

“What is it?” Gavin called down, as his walker scraped across the wood.

As she blinked at the gleaming find, her subconscious registered the fact that he was moving. She spun toward him.

“No, Gee, stay where you are.” The ground began to rumble under her feet, and she shouted, “Move back from the trench. Gavin, move now.”

But as the words left her Jema saw the ladder tilt at a crazy angle and the wall in front of her collapse. Her brother fell from his seat and pitched forward. She dropped the torque as she reached up, hoping she could catch him without breaking his bones or hers. Then the world disappeared from under her feet, and she was sucked into a terrifying void.

Oak tree roots stretched around her, encircling her as she tumbled over and over, unable to see or stop herself by grabbing a handhold. She screamed for Gavin, and saw him above her, his body encased in the same light that had come from the tree roots.

We’re going to die, Jema thought. No one will realize we’re gone. It was only us two.

She finally struck bottom, but there was no bottom, only a tangle of more roots. She clawed her way through them to collide with another wall of stone, this one slamming into the side of her face. As consciousness ebbed, the warmth of blood streaked across her face. Numbly, Jema gave herself to the cold dark that surrounded her, and discovered one final surprise—she was grateful.

Gavin didn’t have to die alone.