The stress and responsibility had worn him out. He struggled to swing his legs over the bed then staggered to the refectory, but the hullabaloo rattled the windows from the outside. Ryder stood in the doorway looking out.

"We've been months in space, circling this planet and you are saying we can't go for a walk?" shouted Adbul at Brian and Derek, who each held a rifle at the astronauts.

Vlad took his turn at bellowing. "Have you people any idea at all what it's like cooped up in a tin box for so long?"

"Why don't you shout a bit louder, boys," Bronwyn said. "Did you shout at each other up on the space station?"

"'Course not," said Vlad, to a Yeah, right from Jena.

"Listen, if you did yell at each other in your tin can, no one would have heard you, would they?" Bronwyn continued, like a nagging schoolteacher. "Whereas out here." She waved her arms at the hills. "Just beyond those echoing hills are millions of people who all have perfectly functioning ears as well as ARIA."

Her admonishment brought silence.

Dan, Jena, and Antonio leaned back on the minibus, each with a steaming mug and saying nothing. Ryder couldn't tell by looking in their eyes whether they were laughing, annoyed, or indifferent. He'd told Bronwyn that the ISS crew were the most intelligent set of people left who still had all their marbles. He knew it would have given her great pleasure to give them a dressing down.

"Ryder, tell them," Brian said.

Ryder waved at the hillsides. "Dan, this valley might look very spacious to you, but we need to have a chat, lay down some ground rules and-"

"I don't like the sound of rules," Jena said. "We've had to live by checklists and NASA protocols for ever. I'm kinda looking forward to a taste of freedom."

"I'm sure you'd rather we all follow a few basic precautions than catch ARIA. It's as easy as meeting a stranger on that hilltop. And then we'd all have it. The end."

"Yeah, come on guys," Dan said, "let's get to business and decide what we're doing with that case."

Friday 18 September 2015: Moraine Lake, Rocky Mountains, five months since Manuel (55) caught ARIA, twenty-two years of his memory gone.

THE MORNING SUN HIT MANUEL'S NIGHTMARE-TORTURED FACE. His hangover beat him up. His ears tried to shut out the irritating tapping noise from someone who was going to get shouted at when he raised enough energy. Eyelids stuck down with sleep struggled to obey opening instructions. His right arm stretched out under the sheet and found warm flesh that wasn't his.

More asleep than awake, he turned to the woman. "Anne, shall I make some coffee?" Then one eyelid inched open, like a portcullis. Confused thoughts about getting divorced from Anne ravaged his brain when he remembered her with blond hair and not the redhead turning in bed to face him. He moved a leg to find the floor as her green eyes found him.

Her scream drowned out the tapping. As he turned from the howling, Manuel caught the blue flash of wings as the woodpecker flew away. The cabin vibrated: every animal in the forest was on the run. Forest? Why was he in a forest cabin? As the screaming from the naked woman (not Anne), continued, he thought about trying to calm her down, but he didn't know how. He assumed they'd had sex by the fact he, too, wore no clothes. Nothing he could think of saying could mitigate the situation, so he found some trousers and wandered off to seek a bathroom.

An old man with almost no hair stared at him from the mirror. It wasn't him. He touched his stubble and his shiny head. He must be in a dream. A note taped to the mirror said, "Kitchen table. The NoteCom. Press Go."

The kitchen in this familiar yet unknown cabin was too neat. The table was bare. What the hell was a NoteCom anyway? A pad could be a notepad, like the ones he used as a journalist. Of course, back in his office, he used a computer to word process his pieces, like all modernised hacks in 1993. Good, the shrieking had whimpered off. He filled an electric kettle and switched it on, noting a dial on the wall indicating 60% solar charge. Something else he hadn't remembered seeing anywhere. The packaging of foods in the cupboard looked different with their plastic-like containers carrying labels embossed rather than stuck on their child-proof sealed lids; the cooker hob had touch-sensitive panels rather than knobs.

A well-thumbed Rocky Mountain What's On magazine lay on the fridge. Manuel shook his head at the March 2015 date. "Somebody's having a joke," he said to himself, and then the bedroom door burst open.

They looked at each other in silence, trying to figure out the who and what had happened, racking their tortured memory for unavailable clues. Finally, Manuel pointed at the bathroom door.

"The bathroom. I'm Manuel."

"I'm pissed off."

"Makes two of us." He made two coffees. No bread to toast or bagels, no fresh foods. He pulled a face at a few packets labelled Humulin products. Maybe his mystery woman was a diabetic. He settled on crackers and opened a cream cheese plastic container with a Use by May 2015 warning. "Should be all right for another few years." A headache fuzzed and the back of his eyes hurt like he was catching a cold, but curiosity drove him, carrying his coffee, into the lounge. He almost dropped the coffee when he saw strange Hi-Fi-type multimedia devices. A large black mirror on the wall took some time to be recognized as a TV. More yellowing papers and magazines confirmed the futuristic date.

He collapsed into a large leather armchair.

"What the hell has happened?"

"When you've figured it out, let me know," said the woman, dressed in shirt and slacks, carrying the coffee he'd made for her. She roamed the lounge, picking up the same papers and magazines, stared at the same unremembered technology, until she sat in a chair opposite him.

"Manuel. Who are you and what are we doing here?"

"As far as I know, I am Manuel Gomez, a journalist specialising in astronomy. I recall a cabin like this in my boyhood. That was in Lake Moraine and the mags and view out the windows verify that. As to why we are here. I've no idea. Last thing I remember was going to bed in my home in Baltimore in 1997. You?"

"This has gone far enough, Manuel or whatever your sodding name really is. You must have slipped me a Mickey in a drink last night and brought me here. Messed me up and put trick stuff in here to confuse me. Where's my car keys? And my car!"

"You're nuts," he yelled back. "I'm as darned confused as you are." He stood, as she did. Two bewildered combatants.

"I'm calling the police," she screamed. "I hope you like prison food, you bastard." She had found the landline phone when she first came into the room. "You've cut us off!" She threw the phone at Manuel, who, unprepared, caught it with his forehead.

"You bitch, you've drawn blood!" His hand dived into his pocket for a handkerchief but only brought out a car key.

She grabbed for it and held it in front of her, first in triumph then puzzlement. The key had a familiar Ford logo in a clear Perspex fob with a couple of press buttons. But the working bit, made of what looked like stainless steel, was a smooth, two-inch glass rod. No familiar twentieth-first-century car key. Her face crumpled into tears as she let the key fall.

Also confused, Manuel examined it. Working with space technologies left him few surprises; he must have picked it up at one of the many conventions he enjoyed. He thought he ought to try a hand at consoling the woman but counter-advised himself. He looked for more clues by returning to the bedroom.

By his side of the bed, he found a digital watch.

0832 09:18:15.

Did the fifteen represent 2015 after all? He slipped it on. He walked round to the woman's side and found a textile shoulder bag. The urge to empty it on the bed fought with the prediction of a huge fight if she walked in, so he carried it to the lounge.

"Shall we see if this bag gives us any clues as to what's going on? Look, I'm in the dark here too. I've told you my name. I can't call you 'You,' can I?"

"Please yourself, I'm out of here." She headed for the door.

"If we are where I think we are, you'd have to walk miles to the nearest town."

"It can't be far to a phone box or to the next lodge. Somewhere with a friendly face, instead of a kidnapper, rapist-"

"You still think that of me? Gee...and I made you coffee. How do you know the next lodge is occupied or the next and the one after? It might be full of real rapists."

She slowed her walk to the door but reached and opened it. "Some things are worth risking."

"Aren't you forgetting something?" He held up her bag.

"It's not mine." She frowned.

"Where's yours, then? All women have a bag; it's a law or something." He grinned at his joke and saw just a glimmer of mirth in her face, but she had good control.

"I don't know. I have a red leather bag. You must have grabbed me before I had a chance to pick it up."

"Right. Let's see what's in here." He turned it upside down on the table. Handkerchief, cosmetic containers, notebook, pens, a change-purse, card-wallet, and a cell phone fell out. She stayed at the open door, but her mouth gaped at the sight of the distinctive red leather purse. Manuel picked up the card-wallet. "Julia Tyndall of Washington?"

She rushed over, snatched the wallet and purse. "You're a thief as well."

"I think even you must be doubting these instant reactions of yours." He picked up the phone. "Well, look at this. I thought it might be a calculator, but it unfolds with a little screen. Damn me if it isn't a phone. Mine's more of a talking house brick. Look at it."

"That must be mine too," she said, more sulkily than angry. "Give it to me." She punched at it but it was lifeless.

"Would you check your notebook out, Julia, or may I?"

"Mrs Tyndall to you," she snapped, grabbing the notebook and sitting on one of the stools around the table. She spent some minutes in silence while Manuel put a plate of crackers and cheese together for her and fetched her coffee back from the lounge. As he sat opposite her at the table, she closed the notebook, looked him in the eye without giving away any expression. She tossed him the notebook.

Shopping lists made up the first few pages. Manuel looked for clues; both to find out where twenty-two years had disappeared to, and how the two of them had crashed together in this cabin. He scrutinised a few more pages. Some items made him think maybe he was in 2015: KwikMart Eggs, Cheese, Bread-low fat multivit organic wholeml Mike's medication-Seratonin patches Memory bubble stick-100 TetraByte - the $20 special offer NoteCom case Who heard of organic low fat bread at a KwikMart? Who's Mike and patches for medication? He guessed at the computer memory components, but as far as he remembered, a TetraByte was a thousand GigaBytes. Sheesh, that's more than the whole space program uses-or used-in the 1990s. Manuel remembered the mention of a NoteCom on the bathroom mirror.

He examined a more recent page: Travel toiletries Pick up flight tickets Washington 2 NY, NY 2 London Job swap documents Then a dated page: Thurs 23 April on Dreamliner flight La Guardia to London. Everybody sick-headaches, confused. My papers remind me I'm meeting family who already have ARIA but some passengers can't remember why they're on the plane!!!!

Mutiny-the flight crew ill or dead. A passenger who was a pilot flew the plane.

Going back to America. Dizzy.

Friday No one answers phone at home. With others I walked out of isolation hospital-staff there weren't around this morning. Going to try and get back to Winnipeg-somehow more family there.

Manuel flipped through some scribbled pages of confusion of Julia's dreadful state and journey via lorry and car lifts, hiding out in Toronto and Port Arthur-until the last page: Sept 16 Banff-sticking with M. A good man. Lost his wife Jat according to his NoteCom. Heard my family aren't in Winnipeg any more. Manuel also worked NASA at Goddard but I don't remember him. He knows my boss Karen and her brother, Ryder-so do I, apparently.

Manuel looked up at Julia. She shrugged, and he took the gesture as an apology for all the earlier bawling. "Good idea; keeping notes," he said. "If we're still here tonight, we should write a big one for the bedroom ceiling. Looks like I have some useful information in something called a NoteCom. I ought to look for a holdall. Maybe outside, left in my-our-car, or something. Any ideas? And any notion as to what ARIA actually is?"

She shook her head. Tears dropped to the magazine on the table followed by her head as she sobbed. Manuel stood, walked around behind her, and patted her shoulder as he passed to the door and out in the hope of clearing his head with a walk and finding his NoteCom. How many mornings had started with shock, horror, and reconciliation like today?

Saturday 19 September 2015: Anafon Field Centre. Many people outside the valley will have lost up to twenty-three years of memory.

AFTER THE UNEASY START WITH THE ISS CREW arguing with the centre staff, Ryder woke determined to make a positive, new beginning. They'd sorted a few ground rules then split up into three tour groups. Tour one looked at the centre's facilities. Tour two took in a long walk around the Anafon valley perimeter with additional advice to keep away from the sheep and feral ponies in case they have ARIA. Tour three, led by Ryder, took astro-engineers Jena and Dan to the abandoned mine where they'd put the case yesterday.

"It's a mile," Ryder said, stuffing a rucksack. "Not far but enough to get soaked in a sudden Welsh storm. The mine goes under the mountain for at least another mile, which is why we're packing rubber boots and head-torches."

Jena pointed at the trolley Ryder had brought round, loaded with the white NASA space-pressure suits. "I assume you want these to act as biohazard protection suits for when we open the case?"

Ryder tried not to stare at her. Her slim features and model-like Euro-Asian face matched an ideal-woman formula in his hormones. Her deep blue eyes shone, but he hadn't dared be drawn into them.

A clearing-throat cough later, Ryder responded. "Yes, even though they won't fit all of us, they're better than our thin disposable suits."

To his astonishment, once ready to go, she linked arms with him as they set off. He glanced back to check Teresa hadn't seen them. Then he remembered she led the valley and perimeter tour with Dr Antonio Menzies and Vlad. Of course, she had binoculars...

It must have been her being cooped up for so long that put Jena in an exuberant mood as she pulled Ryder along. He'd not been chatted up by an American woman before.

"Come on then, what's all the goss?"

"Pardon?"

"Let'r rip, Ryder. Are you and Teresa serious, married and with children?"

"Good Lord, no. But, we-"

"I didn't think so. Nor am I, and I am delicious, aren't I, Dan?" She turned to her commander, who pulled the luggage trolley along the rough track.

Dan looked up, shaking his head in a mild rebuke at her outrageous flirting.

"Just agree, Dan. Actually, he never makes a decision along lines I suggest, so I'll have to rely on your judgement. Am I gorgeous?"

After another cough. "I thought you astronauts would have trouble walking after being in orbit so long. Have you been exercising up there?"

"Ryder, you must have been eyeing me up. I don't mind, did you think I would?"

"No. Yes. I mean-"

"Leave the poor man alone," said Dan. "That's one of those 'have you stopped beating your wife' questions. This is a beautiful valley, Ryder. Incredible, isn't it, Jena?"

"To be honest, the bleakest of wide-open moorland would feel like heaven compared to that tin can with four morons. No offence, Dan."

"We chose this valley because of its difficult access rather than any intrinsic beauty but, yes, we're lucky to be in one of Wales's best kept secrets."

Dan beat Jena to another question. "How many intruders have you had to kill?"

Ryder raised an eyebrow.

Jena said, "Hey, why the surprise? Oh, I get it, you told the centre group you all had to be tough on strangers and they objected. Yeah?"

"Nothing gets past you, does it?" Ryder said. "You guys are used to making life-and-death decisions. Trained to be hard, whereas my friends have had hardness thrust open them."

"So to speak, eh Ryder?" Jena said, laughing. She spotted the mine entrance and disengaging Ryder's arm, broke into a jog.

"Take no notice of her. She ate men for breakfast before our ISS mission. Then had to behave, cooped up with four men married to their work. Well, except for Antonio, but Jena isn't his type."

Ryder laughed. "And who is his type? Vlad?"

"No. Antonio isn't gay, as far as I know, but he's attracted to European women with unusual features."

"Hah. What? Like no eyebrows or long noses?"

Dan looked away. "More like straw hair, freckles..."

Ryder stopped walking. He didn't need to say that Dan had just described Teresa. Even less did he want to mention their rocky relationship. On the other hand, their relationship thrived on friction. He smiled more when he concentrated on physical problems to solve rather than second guess what Teresa wanted. Relief at reaching the mine entrance washed over him.

"Jena!" He had to shout at her. "No, don't hit the padlock with a stone. I have a key."

Dan shook his head as if to apologise for the lack of behavioural control over his crew. Ryder acknowledged the gesture with a knowing look. They'd both had to deal with difficult people.

"If you had broken the padlock, you wouldn't have been able to get in-"

"Nothing can stop me getting what I want, Ryder."

"-without security cameras seeing you, and by the time you came across the next locked gate, you would have two or more firearms pointing at you."

"Excellent," Dan said. "And as we discussed earlier, it's safer to shoot first and ask questions after, so give it a go, Jena."