The rap at the door was sharp and peremptory. Not the knock of someone collecting for a Christmas charity or a random vacuum cleaner salesman. Besides, it was just before midnight and it was snowing steadily outside. Not the kind of weather for chance visitors.

Jack's head jerked up and his muscles tensed. Without volition, his hand moved to his Webley pistol, drawing it noiselessly from its holster. Very few people knew that he was here, and that was the way he liked it.

Cautiously, he got to his feet, and made his way down the dingy passageway leading to the front entrance. Away from the crackling fire, the air was cold enough to condense into white mist in front of his face as he breathed. The old boards creaked ominously under his feet. Inwardly, he cursed at the betraying noise and hoped none of them were rotten enough to give. Beyond the old-fashioned, semi-opaque glass panels inset into the door, he could just make out the outline of a shadowy figure, waiting on the doorstep.

Holding his arm straight down at his side, the gun concealed in the folds of his heavy military coat, he swung wide the door, his eyes hard and alert. Standing outside, with his back to Jack, was a stocky man in a black overcoat, the shoulders dusted with white flakes of snow. At the sound of the door opening, he turned, revealing a familiar handsome, ebony-skinned face.

It was an effort for Jack to keep the surprise from his expression, but somehow he managed it.

"Rex," he said, his tone wary as he greeted his visitor. The CIA agent was a friend, of sorts. Together, they had taken down the Miracle and saved the world. But that didn't explain why he was here now, in Wales, a week before Christmas, standing on Jack's doorstep in the middle of the night.

"Hey, World War Two," Rex responded. He nodded towards the gun held at Jack's side. "Jumpy as ever, I see."

"Yeah, well, you know me. I really hate carol singers," Jack quipped.

"You gonna ask me in, or do I have to stand out here all night in the snow?"

Jack hesitated, his eyes scanning the quiet street outside for any threat. He could never be sure he wasn't being watched. This could be some sort of set-up. At the very least, Rex could have been followed. However, he couldn't see anything strange or out of place. The surface of the road was covered with a fresh layer of pristine snow, glittering under the urine-yellow street lamps, and a chill breeze whispered through the leafless trees that lined the street. Nothing moved, not even a stray cat. It was almost too quiet.

He made a sweeping gesture with his arm, stepping back to allow Rex to enter. "Mi casa es su casa."

Once the other man was inside, he closed the door firmly and flipped the locks. Only then did he holster his weapon and turn to face Rex.

The CIA agent was looking around the grimy entrance hall, one eyebrow raised as his quick eyes took in his surroundings. "Nice place you got here. I like what you've done with the décor. Dust and cobwebs. Very gothic. Very you."

The house belonged to Jack. He'd bought it long ago, back before the turn of the century, and had all but forgotten about it. It had never been much to look at – tall and thin, sandwiched in between two other dwellings of similar ilk.

Since then, like so much of Cardiff, the area had moved onwards and upwards, renewed and renovated and gentrified. The address on the left was now an upmarket architect's office. The one on the right was frequented by people interested in undergoing discreet plastic surgery.

Jack's house had remained just the same, empty, slightly dingy, a little run down at the heel. He'd had many offers to buy it over the years, via his solicitors, from bright-eyed young developers, their eager, greedy faces lit with the desire to make a profit. He'd turned them all down, even though he hadn't visited the house in years.

He was glad of it now. With the Hub destroyed and most of his team dead, he'd had nowhere else to go, once he'd returned to Cardiff after the Miracle had ended. The interior was cold and spartan, ill-furnished and bleak, the rooms blanketed in a thick carpet of dust and festooned with spiderwebs.

"It's temporary," was all he said to Rex. He had no intention of explaining that he still hadn't decided for sure whether he was staying on Earth. After all that had happened, commitment was beyond him. He was content just to live from day to day, without giving much thought to the future. He was here now, today, at this moment. And that was all he could guarantee.

He looked the other man up and down. Outwardly, Rex hadn't changed much in the year since he'd last seen him. The same dark suit, worn under his overcoat; the same white, open-necked shirt. The same closely-cut dark hair, worn almost in a military style. The same half-belligerent curl to his lip, which said that anyone who dared to get up in his face was going to regret it.

Inwardly, though... there was a weary look in his eyes that hadn't been there before. A dull resignation, mixed with a spark of simmering resentment and anger. Jack knew those emotions, he was one of the few people on Earth who could understand them. He'd seen them often enough, centuries ago, back when he'd first become an immortal, reflected in his own eyes, every time he'd glanced in a mirror. The struggle for acceptance of their condition wasn't an easy one. And he guessed that the CIA agent was stubborn enough to make it even more difficult.

"What are you doing here, Rex? What's happened?"

Rex snorted. "Can't one old buddy make a Christmas visit to another old buddy without there being some sort of problem?"

"When it's you and me?" Jack raised a sardonic eyebrow. "No. So come on, spill. What's going on?"

"Fine. So there's something. But is there somewhere warmer we could discuss it? My buns are freezing off out here."

"There's a fire through here." Jack led the way down the corridor, to the living room at the back of the house. All the rooms they passed were dark and desolate, filled with nothing but the looming, ghostly shapes of dust-sheeted furniture.

The living room looked marginally better than the rest of the house. It was cleaner, for a start, and warmer. The fireplace was bright with cheerful, crackling flames. Several ragged old armchairs were grouped around the hearth, where an old packing crate was serving as a low table. There was a pizza box still sitting on it, containing the remains of Jack's dinner. Not a particularly nutritious meal, perhaps, but it wasn't as if he had to worry about high cholesterol. Over to one side, there was a camp bed set up, with a couple of pillows and an ancient patchwork quilt. Beneath it was the faded old rucksack that held all the worldly goods of one Captain Jack Harkness. It wasn't much to show, some would say, for over two thousand years of life. But time and experience had lessened his interest in material possessions. The days when he had been an intergalactic conman, living on the edge for the sake of a profit, now seemed very far away.

He sat down in one of the chairs, and gestured Rex into the other, reaching as he did for a whiskey bottle sitting within close range.

"Drink?"

Rex plopped himself down and held his hands out to the fire. "I thought you'd never ask."

After fishing around on the makeshift table for a moment, Jack managed to produce a couple of plastic tumblers, which he filled generously.

The other man accepted one and raised it to Jack in a mock salute. "Cheers!" Then he tossed the neat alcohol back like water.

Unwilling to be out-matched, Jack did the same, feeling the burn of the amber liquid as it poured down his throat and warmed the pit of his stomach. Whatever Rex had to say, he figured it could only be improved by a slug of exquisitely aged single malt whiskey.

"So?" he prompted, eyeing the other man narrowly.

Rex took the bottle and poured himself another shot, before leaning back in his chair, his dark eyes fixed on Jack's face. "So... last night, I got a phone call from an old pal of mine. He's currently on secondment to the Home Office in London. It seems they've been looking for you."

There was a slight hiss as Jack exhaled between his teeth. "Is that right?"

"Apparently, they lost track of you in the aftermath of Miracle Day." Rex hesitated. "They need your help."

"The last time I tried to help the British Government, they planted a bomb in my stomach and blew both me and my secret base to hell," Jack replied, a shade of bitterness colouring his voice. "So you can see why I might not be too eager to volunteer my services again."

"Yeah, well, that was a different administration. And believe me, Jack, I get why they might not be on top of your Christmas card list. But people are dying, and not in a nice way. According to my buddy in the Home Office, there's evidence of alien involvement."

Jack leaned forward to grab the poker, stabbing at the embers with unnecessary force, his usually-mobile mouth a thin, hard line. "So? Let UNIT deal with it. Last I heard, the government wasn't gunning for them."

"UNIT are spread too thin, mopping up after Miracle Day," Rex said patiently.

That much, Jack could believe. After all, it wasn't as if he and Gwen had been sitting on their hands. They'd been flat out doing much the same thing as UNIT, just in a less official capacity. After the events of Miracle Day, the world had been in a total mess, just as the Families had planned. Entire economies had collapsed, governments across the globe were in chaos, medical systems were under pressure, and there was general social upheaval, often requiring military intervention to maintain order. Things were gradually starting to repair themselves over time, but it was a slow process.

But the main problem, of which most people on Earth were blissfully ignorant, was that the turmoil on their planet had not gone unnoticed by the rest of the Universe. Jack and Gwen had been run off their feet dealing with alien incursions. Some of them were merely inquisitive, such as the boisterous group of young students from the Anthropology Department of the University on Thogost, bent on enjoying a field trip to a primitive planet. However, some of them were not so benign, such as the scouting party for a Sontaran war fleet that had turned up a few weeks ago, seeking to take advantage of the confusion across the world to launch an invasion. Jack had his work cut out for him, using every resource he had available, to keep the Earth safe and to put out the message to any other extra-terrestrials watching that the planet was still protected.

Whatever threat the Home Office had detected, it had obviously slipped under the radar while he was otherwise occupied.

"What do you want from me, Rex? And why are you involved in this anyway? It's a bit out of your jurisdiction, isn't it?"

"I figure, after everything that happened back at the Blessing, Torchwood's stuck with me and I'm stuck with Torchwood," the CIA agent responded gruffly. "And if I'm a still member of the team, that makes this my jurisdiction. If it's alien, it's ours, right?"

"Yeah." Jack observed him closely, trying to wrap his mind around the implications of having another immortal on the team. Or having another immortal /anywhere/. He was so used to having to carry the burden alone. "How did you find me, anyway?"

Rex shrugged. "Gwen and I have kept in touch."

That wasn't so surprising, even though Gwen had never mentioned it. She had always been the beating heart of Torchwood, the one that brought compassion to their work. It would be like her to want to keep an eye on Rex, after the shock he'd experienced when he discovered what he had become.

"All right... fine. Let's just suppose, for argument's sake, I was willing to help. Exactly what do the Home Office need me to sort out?"

Reaching into the pocket of his overcoat, Rex produced a small packet. One by one, he drew out some photos – ten in all – and laid them on top of the pizza box in two neat lines.

Jack glanced down at them. The images were all similar, depicting human remains, each of them apparently mummified. The bodies were shrunken, as if every drop of moisture had been drained from them, leaving the flesh dry and desiccated, stretched tightly over the bones. Hollow eye sockets stared back at Jack, gaping jaws grinned. At a guess, he would have said they were ancient, maybe even thousands of years old.

Rex must have guessed his train of thought, because he said curtly, "Less than a month ago, all these people were walking around, as hale and as hearty as you and me."

"Who are they?" Jack asked. Despite his disinclination to have anything to do with the Home Office, his curiosity was stirring. This was exactly the sort of case Torchwood had once handled, back in the old days. Back when the Hub had still existed, and Ianto had been alive, and Owen, and Tosh. Back when everything had made sense. "And what happened to them?"

"They were all tourists, who went walking in the Brecon Beacons, here in Wales. And never came home." Rex had a deep frown on his face. "As for what happened to them, nobody knows. Apart from the fact that their bodies have been completely exsanguinated. According to the autopsy reports, it occurred through the pores of their skin. They literally sweated blood until there was none left. I've never seen anything like it before."

"Some sort of disease?"

"Nothing that's shown up on the path reports. And no sign of any toxins either. These were perfectly healthy human beings who bled to death in the space of a few, excruciating moments."

"Living in the countryside isn't always as good for you as it's cracked up to be. It wouldn't be the first time something strange went on out in the Brecon Beacons," Jack said, thoughtfully rubbing the back of his neck. "Last time I investigated tourists disappearing out that way, I turned up a nasty little nest of cannibals. Not the sort of folk you'd want asking you over for dinner. Not unless you were happy with being the main course."

Rex pulled another piece of paper from his pocket and unfolded it so that Jack could see. It was a map of the Brecon Beacons, marked in red with a rough circle, scattered with Xs. "The other strange thing about these killings is that if you plot the locations where the bodies were discovered on a map, they form an almost perfect circle. With the village of Adnewyddu dead in the centre."

He extended a stubby forefinger to point at the red dot that represented the place he was talking about.

Jack smoothed some of the creases from the map, studying it carefully. "So... what do we know about the village?"

"It's a tiny, out of the way little place. Not much more than a general store, a pub and a church, surrounded by a cluster of houses," Rex shrugged. "Population of around one hundred and fifty, from what I can gather. They get a mention here and there in the tourist guidebooks because there's a circle of standing stones on a nearby hilltop. That's the only thing even remotely interesting about it though. The Cardiff police have been through it with a fine tooth comb, but they didn't find any connection to the bodies."

"Yeah, well... that doesn't mean there isn't one." Leaning over, Jack methodically banked the fire and pulled the screen across the fireplace. Then he got to his feet. "Come on, then. Let's go check it out."

"What... now?" Rex said, with some surprise. "I just got here."

"You wanted my help, didn't you? No time like the present. Unless you've got some place else more pressing to be. In this weather, it could take us a few hours to reach Adnewyddu."

As he spoke, Jack pulled out the Webley, and double-checked that the bullets were chambered correctly.

With a low-voiced curse, Rex levered himself wearily out of his chair. "You know, I'd almost forgotten how goddamn annoying you can be, Harkness."

Jack grinned in genuine amusement. "Then it will be my pleasure to remind you, Agent Matheson."

And leaving Rex to follow, he strode towards the door, his greatcoat swirling around his ankles.