Shaun was nervous and wondered if they shouldn't just leave any possible engine monsters to the professionals. He wasn't qualified to fight monsters. He was just an HVAC repairman. And Donna was a temp – whatever that alien had done to make her so insanely sure of herself, she certainly wasn't any more qualified than him. And Rose – okay, there was no telling whether Rose was qualified. He'd thought she looked and sounded like some mid-20s estate girl from South London when he first met her, but not a thing she'd said had made an ounce of sense to him since then, other than "hello," and "pass the butter." He had no idea what her work experience was, if any, and she'd clearly been running around with aliens so long that she had no idea what normal human reactions should be anymore. Their disastrous first trip – kidnapping, almost, in his case – to Venice had been the most terrifying, horrible experience of his life, and she'd laughed and called it romantic. Like nearly getting murdered by vampires was some kind of double date. He had tried, really tried, to be open-minded about his wife's friends, and had even allowed himself to be taken far out of his comfort zone in the effort to be accommodating, but they didn't seem to be making any similar effort to meet him halfway, and he was feeling rather bitter about it.

Now they were leading him against his better judgment toward a set of doors that were clearly marked 'employees only' on a spaceship full of monsters and bizarre, half-human nightmare creaturesin order to stir up trouble where there was none. They passed a human french-kissing and groping what looked like Big Bird against a wall, and he couldn't help experiencing a jolt of shock and disgust.

"Oh, my god…"

Donna, who was walking beside him, glanced at him, oblivious to the horrifying moral, cultural, and genetic degradation of the future of the human race going on all around them. "What?"

"That bloke! Back there!" Shaun hissed back. "That's disgusting. That's like… that's just… bestiality!"

Donna glanced back and huffed. "Oh, get a grip. They're both sentient lifeforms. They're probably married and on their honeymoon. Honestly."

Somehow it disturbed him even more that Donna didn't seem disturbed at all. What were these people doing to her?

They reached the crewman stationed at the door and pulled up to speak with him. He also turned out to be alien, a fact which only became apparent when he opened his mouth to speak and another tiny mouth came out of his throat where his tongue should have been to do the actual talking. Shaun suffered an immediate, involuntary gag reflex which manifested audibly as a sort of "guh" sound. Donna promptly stomped on his foot, smiled sweetly at the crewman, and made excuses for him.

"Don't mind him, he's just got out of a drug-fueled stupor. Plastic surgery, you know. Looks have improved a fair bit, but he's stoned out of his mind."

The dual-mouthed humanoid's interior mouth opened in an 'O' shape. "Ah," he said with raised eyebrows. "And how can I help you vertebrates?"

"Hello! Yes. I'm the Doctor, Chief Department Head for Transport in the Tri-Galactic area, and I happen to be an engines specialist for Minerva-class luxury liners. I understand you're having some trouble with your starboard rotor, and since we were onboard, thought we might lend a hand. This is my colleague, Rose Tyler, and the woman behind us is a temp who's working for the agency, Donna Noble."

"I'm not a temp, actually. I'm an heiress," she contradicted.

"She's a temp," the Doctor repeated with a knowing nod at the crewman.

"I'm an heiress."

"And who's that?" asked the crewman, eyes moving uncertainly over to Shaun. The Doctor looked over with some surprise.

"Oh. He's, uh… He's an intern. You know how it goes. Powerful uncle, useless nephew, pawns him off on some unsuspecting civil agency just trying to do its job. Can't get rid of him or the whole department loses funding. So, shall we?"

The crewman looked uncomfortable and unwilling to go so far as to admit there was a problem, but he tapped a few commands into the computer interface at his desk, verifying the Doctor's introductions with the ship's register. Finally he picked up a 1930's style receiver from its port in the wall and spoke a few words to the bridge. After a minute, he put it back down and turned to the team.

"The captain would welcome your expertise, and asks that you join him on the bridge."

…

Before they were able to enter the employee only areas, all four of them had to have their bio-signs scanned and entered into the system as approved visitors. The ship's automated security system would set off alerts and trigger a lockdown if anyone without the proper approval set foot outside the passenger areas. It was one of many ways the cruise line assured the safety of its wealthy clientele, who might otherwise be at risk of abductions for ransom.

Once on the bridge, they met Captain Manning, a young chap with a pale, sweaty face and clammy hands. Captain Manning, it turned out, did have several years of experience as a ship's officer, but this was his first voyage as a captain. He'd only just been promoted, and was worried his bosses would think he'd mucked up already. Of course, with his luck, the computer system would suddenly start acting up only three days out of port. This had never happened before on any cruise he'd done. It was practically impossible. They had redundancies for this sort of thing. That was the sort of hand fate held for him. He was feeling rather sorry for himself.

"What happened?" the Doctor asked.

The captain popped an antacid and grimaced. "Ship's navigation and steering's seized up, quit responding to commands. We tried rebooting the whole system, but it came back up blank and now we can't even view our current trajectory."

"What about the back-ups? Ship like this, you must have at least two or three."

"We have, but only our onboard technicians can access them and both of them have gone missing. They aren't responding to their pages."

The Doctor looked at him sharply. "Okay, that's a little too inconvenient to be a coincidence."

"Can't you find them with a shipwide scan?" asked Rose. "You must have bio-scanners or something built into each deck, since you registered us on the way in."

"We've tried that," answered the captain. "Either biometrics is acting up or they're not on the ship anymore. Only I don't see how they could've got off." He clutched nervously at his short cropped hair with both hands and returned to pacing the bridge. "We'd get an alert for any ship docking or lifepod ejecting, or… or airlocks opening," he added grimly. "They've got to still be onboard."

"Could be sabotage," said the Doctor. "Other than the technicians, has anyone else disappeared? Crew? Passengers?"

The captain and the bridge crew stared at him in confused disbelief. It was obvious that they hadn't even considered it. "That isn't possible," the captain protested. "It's got to be a malfunction. You don't understand our security systems. No one gets into the vital systems areas without prior approval, and you're the only non-employee we've let in since our official overhaul at our last port of departure."

"Maybe it's an employee."

"No, there's no way. The background checks for employees are… well, let's just say the cruise line is known for being more paranoid than the dictator of Galaxon 6. An employee wouldn't do it, and alarms would've gone off if anyone other than an employee entered a restricted area. The biometric scanning system is perfect. You can't turn it off, and you can't fake biometrics. It's scientifically impossible."

The Doctor inhaled through his nose and tilted his head back thoughtfully. "Weeelll, I can think of a few ways. A plasmavore could do it. Or you could program a force grown clone. Or the easiest way, just slip on a biodamper."

The captain stared at him in horror. "A what?"

"Biodamper." The Doctor popped a ring box out of his pocket and gestured at it. "Blocks all bio-signs. Ship's security system wouldn't even recognize anyone was standing there at all, would see just a lifeless room. I've got one here." He opened his box, but it was empty. "Ah, right. Donna has it."

"No, I haven't," Donna denied flatly with a shake of her head.

"What?" The Doctor turned to look at her in dismay. "What'd you do with it?"

"Well, it reminded me of Lance, didn't it? Chucked it in the secondhand bin at Barnardo's."

"That was a perfectly good biodamper, Donna!" he complained. She shrugged.

Captain Manning interrupted them. "Hold on. Nothing can block bio-signs. There's no such thing."

The Doctor just looked at him patiently. "Sure, there is. Would've been invented… Oh, this is 12th of May, 5145, so let's see… Five months ago? The first prototypes should just be hitting the black markets now."

The captain stared at him in horror. "You're saying with a… a biodamper, any of the passengers could have gotten into the restricted areas and they wouldn't even show up on the computer scan?"

"Yeah. You got your entire crew and passenger list accounted for?"

The rather alarmed crew stood frozen for a second. Then Captain Manning turned and started giving orders to check all bio-signs currently being monitored against the passenger and crew list, and find out how many people had disappeared off the biometrics scans.

The Doctor used this opportunity to start looking over the frozen steering program on the nav computer. He tapped a few buttons experimentally, then knelt down, removed the panel covering the computer terminal's primary hardware, and started sonicking things inside.

"Sir, we can't find four of the passengers. It's the Sullivan party in 36C," one of the crewmen announced.

The captain spoke into his comm link and gave orders for the cabin stewards on the passenger deck to get down to that suite and check it out, quietly. In the meantime, crewmen in the dining hall and on the top deck reported in that no passengers matching the Sullivan party's descriptions were in either place.

The captain downed two more antacids and paced the bridge. "Oh my god, oh my god…"

Feeling sympathetic, Rose patted him on the shoulder. "Look, why don't you get the passengers involved and do a shipwide search? Hand out photos and ask everyone to report in if they see them. Biodampers won't make the wearer invisible, after all."

The captain stared back at her in horror. "Are you kidding? People will know something's wrong. There will be a panic. And the Minerva Cruiseline's selling point is its absolute safety. It's more than my job's worth to harm the reputation of the company."

The Doctor got the nav computer unfrozen just then and picked himself up off the floor where he'd been kneeling. "Right! Now that that's working again, let's see where you're taking us."

He entered in some commands, and Rose, Donna, and a few nearby officers peered over his shoulders to watch.

"We're on our original course through the K'ribb-dees orbital path, already pretty far inside the official danger zone… Stay on this, and we'll pass within kilometers of the planet's outer rings. Can't have that…" He tapped a few more buttons, and a pop-up window appeared on the screen and beeped at him.

COURSE ALTERATION UNSAFE. NOT RECOMMENDED.

"Really," the Doctor remarked dryly at the computer, "Except our current one isn't all that safe either. Let's try this again, shall we?" He plotted a different detour.

COURSE ALTERATION UNSAFE. NOT RECOMMENDED.

He hummed. Rose shot him a sidelong glance. "Doctor? What if our course doesn't get corrected? Will we crash?"

"Ohhhh, I shouldn't think so. The rings look thick, but where we'll end up is mostly dust. The shields can handle it. I'd be more worried about the radiation."

"We can handle the radiation, sir, if it comes to that," said the ship's first mate. "The Hindenburg's got the best shields in this quadrant of the galaxy. She can withstand radiation levels up to Oseidon level if necessary, but that's not the biggest worry. The plasma bursts are."

The Doctor looked at him in surprise. "What? Plasma bursts won't go out that far. There's nothing to ionize outside the planet's atmosphere."

The bridge officers exchanged glances. The captain looked like he was going to be sick. The first mate leaned forward and, in a low voice, explained. "There's something weird about K'ribb-dees. Fifty years ago, a royal envoy from Draconia was passing through this system. This was back when their emperor was an empress, and she was on 'er way back from some diplomatic function. Somethin' went wrong, and they stopped responding to subspace communications. The ship was late returnin', and the radiation from the planet was messin' up radio contact, so the Draconians sent some ships to go see what 'ad 'appened. The ship was just lying there, dead, in the rings, shields fried, and no response. When the salvage teams went in to try to tow it out, they say, the planet started shootin' plasma bursts at 'em. They weren't even as close as the rings yet."

Donna and Rose listened with interest, fascinated by the ghost-story whispers the crewman had fallen into while telling it, and the way the other officers in the bridge all nodded solemnly in agreement. The Doctor raised his eyebrows. "Okay. That's odd. Has anyone looked into why?"

"There have been probes, sir, but they're all shot down as soon as they enter the danger zone. There's a reason the planet's been quarantined. And the plasma bursts only 'appen when some ship or asteroid or somethin' flies by, and then the plasma will reach out like an arm from the planet's depths, and just, BOOM!" He clenched his outstretched hand into a fist in a dramatic interpretation of a conscious malevolent planet destroying a helpless spacefarer. "Something's living there, sir. It's said the plasma's some kind of weapon."

"Whose weapon?" the Doctor asked, matching him hushed whisper for hushed whisper.

"The ghosts of K'ribb-dees."

The Doctor blinked at him for a moment, then waved a hand dismissively. "Ghosts? Nahhhh, no such thing as ghosts."

"But there is, sir! There's no life signs on K'ribb-dees. Nothin' lives there. Barely even a biomass reading in the atmosphere, bacteria and such. But someone's shooting at anyone who trespasses its orbit."

The Doctor let out a sigh and leveled a stern but patient look at the nervous crew. "Look, let's all just put the 'ghosts' theory on hold for the moment, and focus on getting our steering back. Whoever sabotaged the nav computer clearly knew what they were doing, so I'll have to do a system restore to get it working again, and I'll need someone to manually disconnect the maneuvering thrusters in the propulsion section so we don't take off like a Didonian sand beast once the automatic system check kicks in."

The captain directed a look at one of the officers, who saluted and left the bridge.

"Rose, Donna" the Doctor added, turning to his companions, "Oh, and, er….. Shaun. Go ask around and find out if anyone's seen those missing passengers. I'm gonna stay here and work on getting the steering back online."

"Yeah. On it." Rose nodded and headed for the door. Donna turned after her, followed by a dismayed Shaun.

"Oh, but don't draw attention to yourselves!" the Doctor called after them. "They're probably the saboteurs. We can't let them know we're on to them. Just keep an eye out and don't do anything risky."

"All right! We know what we're doing," Donna shouted back from the hall, shaking her head at him even though he couldn't see her. "We're not exactly new at this, you idiot."

…

In the hall, Rose caught her heel on the carpet and narrowly avoided an undignified face-plant.

"Damn," she muttered.

"What's wrong?" Donna asked.

"I can't run in these," Rose explained. "Look, I'm gonna just pop back to the TARDIS and change first. Meet you back in the dining room?"

"Right. See you in a bit."

Rose turned and headed for the stairs leading down to the deck below, where they'd left the TARDIS, and Donna and Shaun continued on into the dining hall. The crewman guarding the employee entrance stopped them and gave them a paper-thin data pad as they passed.

"Here you are, ma'am. The bridge sent this down for you."

"Cheers. Let's have a look."

She tapped the screen and brought up the basic info on the four missing passengers: three men and one woman. It included their names, port of origin, cabin number, and photo IDs. The photos looked like pretty standard humanoids – almost normal, from Shaun's point of view, except for the unnaturally high foreheads and the fact that the woman wore a towering blonde beehive hairstyle. She was almost pretty, in a kitschy 1960's sort of way.

"Patty Sullivan, movie producer, origin New Atlantis," Donna read aloud. "Traveling with her 'executive assistants,' Joe, Dick, and Harry. Let's see if any of the passengers have seen them."

She waved down what looked like a bipedal carrot and asked about the photos, but he hadn't seen them. She tried a human couple and a Tree of Cheem next, but they didn't have anything for her either. A lady with a pink terrier recognized two of the blokes, but said she hadn't seen them since breakfast, when they'd passed her on the way to the tennis courts.

"What now?" Shaun asked.

Donna sighed and looked around. "Ask someone else, I suppose." Something on the buffet table caught her eye. "Oh, look! Is that Jovian sandbeetle kimchi?" Delighted, she reached for a cracker with some kind of red shavings on top and popped it into her mouth.

Shaun made a frustrated sound and looked away.

"What?" Donna asked.

"Nothin'. It's just, look at you! You don't even like kimchi."

"Yes, I do. 'Course I like it."

"You never did before! You won't even eat calamari. And now you're scoffing down alien beetles and kimchi like you're some whole different person."

"What on earth has got into you?" Donna stared at him. "So I like it now! As a matter of fact, I got a taste for it when I was traveling with the Doctor. It was the local snack on, on, oh what was it, Planet Zog or something, that place with all those fancy sunhats. What's it matter? It's just food."

Irritated, Donna turned away and sucked the crumbs off her fingers. She wasn't exactly thrilled to keep surprising him either, but what could she do? Shaun had met her after she'd already traveled the universe, seen terrible and wonderful things, widened her horizons, and come to find her own place in it all, but he didn't get any of that. How could he? She felt like she had lost a good ten or twelve months of her life being brainwiped, walking around without a clue as to what she'd done and learned, and missing out on all the amazing things out there that she could have been exploring and experiencing. Now, all she wanted to do was to make up for lost time. She couldn't help it if he was going to fall to pieces every time she took a bite of something new.

With a little sniff, she shoved that thought aside. There was no point in picking at old scabs. The Doctor had done the only thing he knew to keep her alive, and she was fine now. Better to focus on the present and really enjoy herself.

She held up her head and picked out her next likely witness among the crowd in the dining hall.

…

Lee McAvoy had been in the aft airlocks, giving the probe a final once-over, and was just walking back into the dining hall to actually follow through on his earlier intention to eat something when he saw her.

Donna Noble, his Donna Noble, was standing by the starboard windows talking to an Avian Varosian, her ginger hair glowing in the chandelier's light, gems sparkling round her neck, smile on her face as she nodded and laughed.

Something seized up in his chest and he stopped, frozen to the spot.

It was really her. Not someone who sounded like her. Not his imagination. She was really here. He knew her face perfectly. He saw it vividly in his memory all the time.

"Donna? What's happening?"

"I don't know, but it's not real. Nothing here's real. The whole world, everything. None of it's real!"

"Am I real?"

"Of course you're real! I know you're real. Oh god, oh god, I hope you're real!"

They been pulled apart then, faded into the light as everyone's emergency teleportation process had finally completed itself, a hundred years late. Her last words echoed through his head.

"I'll find you! I promise you, I'll find you!"

He'd been holding onto that promise for two years since those last moments in the library, when he'd finally glimpsed her in the crowd of evacuees and tried to call to her, but couldn't get her name out in time. Unlike the rest of that dream, she had been real. He'd already known it, felt it somehow even in the false reality. He'd been real, too, it turned out, something that he'd been less sure of up to that point, but it hadn't done them any good. He'd called to her, but got stuck on that first consonant, and hadn't been able to get off the teleportation pad in time to reach her in person.

He'd materialized on the emergency transit station with the others and waited for her to come through with the next group, but she hadn't. He'd been shuffled along into counseling and social reintegration programs with the other victims, and kept looking for her, but didn't see her then either. He checked visitor notices, hoping maybe she'd gotten out another way and would come find him like she'd said, but she never had.

He'd never resented his stammer so much in his life, that one time it was so important to just get the word out and he couldn't do it. It had haunted him.

More than that, her promise to find him had haunted him.

Perhaps it was that the computer had matched them well according to their traits, or perhaps they were both just lonely enough to be content to time-skip straight into marriage, but they'd been happy, very happy. In particular, he'd been really, really happy.

…Had she been happy?

Suddenly plagued by second thoughts, he turned away. What if she'd been repelled by the idea once she'd gotten Dr. Moon out of her head? She hadn't gone searching for him after all, and he'd been easy to find. Maybe she hadn't meant what she'd promised in the virtual world. Maybe it was just the computer putting words into her mouth – or maybe she had meant it at the time, but once she was out and the dreamlike haze of being in the computer had faded, maybe she'd laughed it off, or regretted it, or felt uncomfortable about it, and god, should he maybe avoid her?

He looked back at her in a panic, then turned away again, then turned back to convince himself she was still there, then thought maybe he had better just hide, or look away and look busy, or, oh shit, too late, she was turning, she'd seen him, her eyes suddenly flashed recognition, her jaw dropped open, she broke into a smile, started to walk over, oh god!