Disclaimer: I don't own Doctor Who

A/N: Belated Happy Easter! Or as I like to call it, Belated Happy Chocolate Egg Day!

Under the Lake – Part Three

"So what's the plan?" the Corsair asked, moments after the Doctor had announced his intention to capture the ghosts.

"Excellent question – we know that the ghosts cannot enter the Faraday Cage, so theoretically, if they were to be lured inside, they won't be able to leave it".

"Theoretically?" asked Bennett.

"We need to split up and let the ghosts follow us right into the Cage" the Doctor continued, ignoring Bennett, "First things first, O'Donnell, I need a map of the complex to figure out the optimal route to the Cage" he instructed. The young technician snapped an eager salute and sat down at the bank of computers, cracking her knuckles and getting to work.

Lunn, feeling rather indignant on his boss' behalf, plucked up the courage to demand, "Excuse me, who put you in charge?"

"I did. Do you know anything about capturing unknown hostiles?"

"N-no" said Lunn, flustered, "But this is our base and"- he was cut off by Cass, tapping him on the shoulder. The two of them began to converse in sign language…Clara leaned over towards Flavia and muttered, "What are they saying?"

"She's telling him to listen to the Doctor" Flavia replied, "That we're the only ones who know how to stop these things".

"No, sorry, this is insane" Bennett protested, "We can't go near those things, they…they killed Pritchard. Who knows who could be next?"

"Them attacking us is rather what I'm counting on" the Doctor admitted, "But don't look so worried. You're all going to team up with someone".

"Who's going to lure the ghosts?" O'Donnell inquired curiously, before adding, "Just so you know, I'm totally okay with"-

"Nah, sorry, it can't be you" the Corsair shook his head, "We'll need you to direct us via intercom and seal off areas as we move, to channel the ghosts. I'll go with Bennett, Romana can go with Clara"-

"No, I'll go with Clara, thank you. Romana and Emily can be the ones to"-

"Why can't I go with Clara, dad? We were just talking about this, I'm not a kid anymore, I'm a Time Lady, a universe defender in training! I can handle a few measly ghosts".

"I was going to give you the most important job, darling. You and your mother can lure the ghosts the rest of the way into the Cage…"

"Really?!" she asked hopefully.

"Via hologram" he finished. Emily, naturally, was less than amused by this.

"Seriously?" she huffed impatiently, "Dad, just let me try. We can look out for each other, and I'll be really careful, I promise. Please can I go with Clara?"

His fatherly instincts were all but shouting for him to refuse, to insist it was too dangerous…but, his little girl had grown up, and he'd been sheltering her for a long time…and they wouldn't be in the line of fire, as it were, for very long. The Doctor sighed in defeat and reluctantly agreed, "Very well…you can go with Clara; so long as you both stick together, understand?"

"Understood" she nodded, beaming, and gave him a hug. The Doctor stiffened a bit, but in all honesty he was starting to grow used to the hugs…from Romana, Emily and Clara only, not from anyone else, he was well past the point of hugging total strangers.

"Great, now that's settled, Flavia can go with Lunn"- said the Corsair, only to be interrupted by Flavia declaring, "That won't work; Lunn and I are the only ones here who speak sign language, remember? It makes far more sense for Romana to go with me and for Lunn to stay here, and translate for Cass".

"Ok, fine. I'll go with Bennett, Emily with Clara, you go with Romana and the Doctor can lure them the rest of the way with his holograms. Well, what are we waiting for?"

/

This plan is still insane Bennett thought nervously, as he and the Corsair made their way through the Drum, following the unknown signal on the Corsair's sonic screwdriver. According to the Doctor, if said signal wasn't being produced by anything in the mining facility, it must be the ghosts…a theory that was borne out when they peeked around a corner, and saw the three ghosts gathered together. Ghost-Pritchard was standing halfway through a wall, the alien was halfway up the wall, and Moran was on the ceiling.

They waited for the signal…the lights dimmed one by one, plunging the whole base into an eerie artificial twilight. "Good evening" announced the computer, "Entering night mode".

Bennett and the Corsair exchanged a glance, a nod, and stepped out in view of the ghosts. "H-hey, how's it going?" Bennett asked, the first thing that came into his head, just to get their attention. It worked; Pritchard emerged fully from the wall and turned to face them, the ghosts beginning to advance.

"Catch us if you can!" the Corsair said cheekily, before dashing off to catch up with Bennett, who had bolted pretty much the moment the ghosts started moving. Everyone was being watched via live CCTV in the bridge, by the Doctor, Lunn, Cass and O'Donnell.

"Bennett and the Corsair have got them moving" the latter reported, doing her best to remain professional despite the frissons of excitement running through her at the thought of helping the Time Quintet, "and Clara and Emily are in position".

The Doctor mentally tracked everyone as he scanned a map of the Drum. Emily, Bennett and the Corsair are going to run across the top of the T-Junction to your right, in about ten seconds. You and Clara need to draw the ghosts, but don't let them too close, and take the first right, then second left, remember that he reminded his daughter; they were speaking telepathically, because they weren't sure if the ghosts could hear them, but they didn't want to risk the ghosts overhearing the instructions and plan and not being fooled.

I know, dad Emily sighed a bit exasperatedly. She and Clara waited until Bennett dashed past, closely followed by the Corsair, who shot them a wink as he hurried past. When the ghosts appeared, she called out the first thing that came into her head – "Hey, you! Yeah, come and get us, you…dumb ghosts!"

It perhaps was not the most eloquent of jibes, but it captured the ghosts' attention, as all three paused and turned to advance upon Emily and Clara.

Romana, Flavia, they're coming your way. When Clara and Emily go left, you need to keep the ghosts moving on the same path they are now.

Yes, dear, we know Romana answered with more patience than her daughter, and then we'll go through the flood door fifty yards on our left, and O'Donnell will close it once we're through, correct?

"I can hear them coming" Flavia announced suddenly; she and Romana stepped out of their hiding place, just as Emily and Clara came around the corner. They exchanged brief thumbs up signals and the younger pair ducked into another corridor, moments before the ghosts appeared.

"Well, it took you long enough! Hurry, then, before we get away!"

They turned and hurried down the corridor; Flavia looked over her shoulder to check the ghosts had taken the bait, and much to her alarm, only Ghost-Pritchard was following them. "Romana, two of them went after the girls!"

/

O'Donnell's eyes widened in alarm as she watched the CCTV, and she hastily reported, "We have a problem. They've separated".

"What?"

"Moran and the mole guy are going after Clara and"-

"Emily" the Doctor finished, "I need to get down there, now".

"Wait! We've got to stick to the plan, we can guide them from here" O'Donnell called out, before switching on the intercom. "Clara, Emily, look out. Two ghosts are still on your case, right behind you" she warned them.

"I'm beginning to think we should have let the ghosts in on the plan" Clara commented, when she looked over her shoulder and saw Ghost-Moran and the Tivolian – that was the name, right? – still on their trail. She and Emily picked up the pace, and O'Donnell told them, "There's a flood door around the corner to your right. I can close it from here, once you're both through".

"Listen to me" the Doctor interrupted, "You two need to get through that door before the ghosts see you" he warned them urgently.

Moments later, Emily called out, "Made it!"

"Now, O'Donnell, fast as you can!"

The door marked '17018' slid closed; Emily and Clara leaned against it, trying to pant quietly, as the ghosts marched past…once they knew they were safe, they grinned at each other and shared a fist bump.

Meanwhile, Romana and Flavia were still being trailed by Ghost-Pritchard. We're nearly at the door Romana told the Doctor, as they neared the flood door on their left.

He's right behind you, hurry!

The two of them darted into the storage compartment that the door led to, and O'Donnell closed the door as quickly as she could…but then Ghost-Pritchard's blankly staring face appeared in the porthole. "He saw us" Flavia gasped; she and Romana backed up against the wall, as Pritchard phased through the door; much to the alarm of the Doctor, watching from the bridge. "No, no…Romana?!" he called into the intercom, "Can you hear me? What's happening?"

"There's no intercom in there; or a camera" O'Donnell told him; it was meant to be a spare storage compartment, there were just a few tools in there…

Metal tools, a fact which Ghost-Pritchard took full advantage of as he reached for a wrench hanging on the wall. Flavia tensed; their species might have had thicker skulls than humans, so they'd survive the attack, but she wasn't exactly thrilled at the prospect of being bludgeoned…

Suddenly, the Doctor had an epiphany; "O'Donnell, open that flood door again!"

"Why?" Lunn questioned, even as O'Donnell hastened to comply.

"It's a ghost!" he snapped, frustrated at the slow, pudding brained humans not understanding, and reached out to his wife through their close mental bond. Romana, he's a ghost! O'Donnell's opening the door again, you can escape!

"Get ready" she told Flavia, gripping the other woman's arm. Pritchard swung the blunt object up in the air just as the door behind him swung open – and they made a break for it, dashing for the exit, right through the ghost and into the corridor. Flavia slammed the door shut behind her and they ran for their lives, darting behind a corner and pressing their backs to the wall.

Romana! Are you alright?

Yes, just about she replied with a shudder, never want to do that again, though. It was…cold.

Is he still after you?

Romana peeked around the corner, but Pritchard was nowhere to be seen. No…he's gone. It doesn't matter – we need to stick with the plan.

Right, yes. The Doctor turned to O'Donnell and asked her, "Where are Bennett and the Corsair, are they in position?"

"There" O'Donnell pointed at the screens, "Oh God, look!"

Corsair, there are two ghosts around the corner from Bennett and you.

Yeah, we noticed the Corsair replied drily, eyeing Moran and the Tivolian. The two ghosts were doing nothing but standing there, swaying and muttering silently at each other.

The Faraday Cage is across the intersection and down the corridor to your right. This last bit is down to you.

Well, wish us luck he sighed, before grabbing Bennetts sleeve and stepping out in full view of the ghosts. Once he was sure, moments later, that he'd gotten their attention, he and Bennett ran for it. As they led the ghosts towards the Faraday Cage, Pritchard emerged and joined the chase. "Well, at least they're not split up anymore" the Corsair noted, "Anytime, Doctor!"

When the ghosts came around the corner, Bennett and the Corsair had ducked into another corridor to hide, and Lunn was standing inside the Faraday Cage, looking confused and a bit nervous. The ghosts walked towards him, into the Cage…and right through him. His image flickered, as the door shut and locked behind them. Once he was sure they were trapped, the Corsair stepped out of his hiding place and walked up to the door. "Yeah, that was just a hologram" he told them, smirking, before calling over the intercom, "It worked, we got them. Well done, you guys".

/

O'Donnell returned the base to Day Mode and everyone reunited at the bridge. As soon as she walked through the door, the Doctor pulled Romana into a kiss, both ignoring the Corsair's catcall. He chuckled and made as if to hug Flavia, only to pull back and rather awkwardly offer her a handshake instead. "You err, you did well" he remarked, as Emily's parents hugged her and O'Donnell cheerfully punched Bennett on the arm.

Clara smiled at the reunion and jokingly remarked, "I'm fine, by the way, in case any of you were worried".

"We're glad you're okay, Clara" Romana smiled, giving her a hug as well, "Now, we need the Doctor to bring an image of the ghosts on the screen".

Her husband headed down to the Faraday Cage. He stood outside the door, staring through at the ghosts, who were repeatedly mouthing a silent phrase. "Cass, are you seeing this?" he asked via intercom.

Back at the bridge, O'Donnell reported, "Sonic glasses Wi-Fi locked in, on screen B2".

Cass peered at the screen, frowning, trying to lip read the ghosts and discern what they were saying. She signed something to Lunn, who explained, "She says she can't see them properly. The glass is too thick and they're too far away".

"Open the door".

"What?" O'Donnell demanded, alarmed.

"Doctor, you can't go in there" Clara protested, "They will kill you!"

"They don't have any weapons or access to any of the controls. They can't hurt me, so open the door".

"He's right" Romana said suddenly, giving O'Donnell a nod to go ahead. With some trepidation, she acquiesced and unlocked the door. Down at the Cage, the Doctor stepped through the open door and closed it behind him. He turned to face the three ghosts; Moran stepped forward and reached a hand out towards the Doctor, right through his chest. The Doctor winced at the uncomfortable, freezing sensation and remarked, "Romana was right, it is cold, isn't it? Take away your weapons and you're not so scary, are you? Is that better, Cass?"

With the ghosts right in front of the glasses, Cass was able to read their lips much more clearly. "She says they're saying the same thing, the same phrase, over and over" Lunn explained, translating for her, "They're saying the dark. The score. No, the sword. The for sale? No, the forsaken. The temple".

"What?"

"Yes, she's sure" Lunn insisted, "The dark, the sword, the forsaken, the temple; just that, over and over".

The Doctor frowned thoughtfully. "Dark, sword, forsaken, temple. What does that mean? What are you telling me, big man?" he asked Moran, who naturally didn't reply. "Bennett! I need maps. I think I just worked out what our friend here is telling us".

/

"They're co-ordinates" the Doctor explained, when he'd returned to the bridge.

"How can they be co-ordinates?" asked Bennett.

"Oh, I see" Romana realised, "They don't mean 'the dark' as in an absence of light, they mean outer space".

"Exactly, so whoever's following the co-ordinates knows they're going to another planet" the Doctor nodded, "The sword?" He handed her an apple, a knobby ball to O'Donnell, a table tennis ball to Emily and a Vector Petroleum place pat to Clara, and got them to hold the items up in a straight diagonal line. "Orion's sword. The sword, the three stars, although one isn't actually a star but the Orion Nebula, hanging down from Orion's belt. But if viewed from back here, the Earth becomes the fourth bit of the sword. So, narrowed it down to a planet now, getting closer" he explained, putting the items on the table.

"Then there's 'the forsaken'. Call it a hunch, but I'd say a flooded, abandoned fake town would qualify as pretty forsaken" remarked the Corsair, "So the ghosts are beaming out a signal, leading someone or something to this location, and every person they kill"-

"Strengthens the signal" Clara worked it out, "Another ghost, another transmitter".

"Which is why they sent for that rescue sub" O'Donnell realised.

"They wanted to trap more people here, to kill and turn into more ghosts, to make the signal stronger" Emily said solemnly.

"But why are they beaming out the coordinates? Is it a distress call?" Lunn inquired on Cass' behalf.

"It could be" the Doctor agreed, "Or a warning. Might even be a call to arms. It could mean, come here, they're vulnerable, help yourself. Wait a minute, though. Wait a minute. Do you know what this means? It means that they're not a natural phenomenon. It means that someone is deliberately getting people killed, hijacking their souls and turning them into transmitters" he realised. He didn't seem too happy with the notion…none of them did.

"But what do the coordinates lead to, though?" O'Donnell wondered, "To us? To the ghosts? What?"

"Ah! What the coordinates are for. That is part of the answer to the other question you're all thinking" the Doctor explained, only to be met with blank stares from the humans. "Really? Come on, none of you?"

"Well, we know" the Corsair admitted, "But we're giving them a chance to figure it out for themselves".

"Then why aren't they?" the Doctor grumbled, "Surely just being around us would make you all cleverer by osmosis. What is the other question?"

Cass began to sign something, and Lunn quickly translated, "The temple. The fourth part of the directions. What's the temple?"

"Finally; it's like pulling teeth". The Doctor spread out an old aerial map on the table. "This is the flooded military town. Shops, houses, town square, and this" he explained, one long finger tapping an L-shaped building.

Clara peered at it and realised it looked like… "A church?"

"Whatever the coordinates are for, it's in that church. Find that and you're a hop, skip and a jump to stopping them".

"Wait, you're not suggesting that?" Bennett asked incredulously. When the Time Quintet and Clara looked at him as if to say, 'well, obviously', he nervously protested, "But we're safe now. The ghosts are in the cage. We can get out of here".

"Aw, come on Bennett. You can help us save the day!" Emily grinned enthusiastically.

"No one has to stay" the Doctor acknowledged, "In fact, I would prefer it if you lot went. You'll all get in the way and ask ridiculous questions. But, you know", he gestured to Cass, Lunn and O'Donnell, "you have chosen to protect and serve. You have given yourself to science and the pursuit of knowledge" he reminded Bennett, "None of you have chosen anonymous or selfish lives. Go, and a part of you will always wonder, what would have happened if I'd stayed? How could I have helped? What would I have learned? I want you to go. But you should know what it is that you're leaving".

The crew looked at one another…Cass signed something, and Lunn explained, "Cass says we should go, but everything that happens here is her responsibility now, so she's going to stay. So I, err, guess I should too".

"Well, count me in" O'Donnell smiled, "Who wants to live forever, anyway?"

"Sorry, err, have you gone insane?" Bennett demanded, "We can go home" he told her; she just shrugged one shoulder and grinned excitedly.

Romana put a hand on the young man's shoulders and told him, "We know you're worried, but don't be. Like you said, the ghosts are trapped".

"How can they be ghosts, though?" he asked, half-rhetorically. When no answer was forthcoming, he sighed and remarked, "Well, at least if I die, you know I really will come back and haunt you all".

/

A little while later, Bennett was piloting their drone submarine via virtual reality goggles and remote controls on his fingers. "Okay, the sub is approaching the town square. Which way is the church?"

"North-north-west, one hundred and fifty yards" O'Donnell described, looking at the old map, "That's it. Starboard two degrees".

"What are we looking for, exactly?"

"Something that has the power to raise the dead and turn them into transmitters; I expect we'll know it when we see it" the Doctor remarked drily.

"Wait, I've found the church".

"Can you – I mean the sub, can it go inside?" asked Flavia.

"Yeah, hang on…" Bennett moved the drone sub forward, and the camera caught a large white casket lying amongst the debris of the church grounds.

"Wait, what's that? Move closer" the Doctor instructed. When he'd gotten a good look at it, he ordered Cass…and then asked politely, at Romana's behest, to have it brought aboard for further investigation. With a bit of careful manoeuvring by Bennett, which earned him a cheerful clap on the shoulder from O'Donnell, they managed to move it into the main hangar.

"It's the suspended-animation chamber from the spaceship" the Doctor explained, as they stood looking at the large white box.

"So the pilot could be in there" guessed Clara.

"There's something inside there" he agreed, "But it's deadlock sealed. We can't open it".

"Y'know, I keep getting the weird feeling that it's not the pilot in there…but who else could it be?" the Corsair wondered.

"Mm-hm. More questions" the Doctor sighed, frustrated, "Everything we solve, just leads to more questions".

"Let's go back to the beginning" Romana suggested, "When we arrived, we found the ghosts but they didn't attack us immediately. They led us here, to the spaceship…and then they tried to kill us".

The Doctor walked inside the spaceship and peered at the markings carved into the side. "Not translated by the TARDIS" he muttered, "Why?" He wiped off his sonic glasses and put them on, looking at the markings once more. The glasses whirred, scanning; he took them off and emerged from the spaceship, walking up to Cass. "Lunn, translate for me" he instructed, before addressing Cass directly. "When we're not around, you're the smartest person in the room. So, tell me, what's weird about this?"

"What isn't?" the Corsair quipped; Flavia shushed him with a glare.

"I know that it's all bonkers but, you know, when you think about it, one thing keeps snagging in your mind. What is it?" he asked her, ignoring the Corsair.

Cass replied, via Lunn, "The markings on the inside of the spaceship".

"The markings on the inside of the spaceship" he repeated, "Yes! Why?"

"I don't think they're just words".

"They're not. They're magnets".

"Magnets?" asked Bennett, "How?"

"Well, a localised and manufactured electromagnetic field, to be precise. The dark. The sword. The forsaken. The temple. When we heard the coordinates for the first time, did anyone expect them not to be that?" he asked them…almost all of them realised that no, they hadn't been that surprised. "No, exactly" the Doctor nodded, "Me neither. It's like we already knew, somehow. Like the words were already in us".

"So that writing is the co-ordinates?" O'Donnell asked, trying to understand.

"Everything we see or experience shapes us in some way" the Doctor explained, "But these words actually rewrite the synaptic connections in your brain. They literally change the way you are wired. Clara, why don't I have a radio in the TARDIS?"

She blinked, and innocently replied, "You took it apart and used the pieces to make a clockwork squirrel".

A few of them stifled sniggers. The Doctor pointedly ignored this and continued, "And because whatever song I heard first thing in the morning, I was stuck with. Two weeks of Mysterious Girl by Peter Andre. I was begging for the brush of Death's merciful hand" he grumbled, a touch melodramatically. More snickers were muffled behind hands. "Don't you see? These words are an earworm. A song you can't stop humming, even after you die".

"Okay, so, the spaceship lands here" Clara decided to sum everything up, "The pilot leaves the writing on the wall so whoever sees it, when they die, they become a beacon of the coordinates, while he slash she slash it snoozes in the suspended-animation chamber".

"Waiting for his slash her slash its mates to pick the message up" the Doctor agreed, "My God. Every time I think it couldn't get more extraordinary, it surprises me. It's impossible. I hate it. It's evil. It's astonishing. I want to kiss it to death".

"Make your mind up, dearest" Romana teased with a grin; moments later, an alarm blared loudly, and everyone looked up in surprise.

"Attention, all crew" the computer intoned smoothly, "Evacuate base immediately. Emergency protocols have been initiated. This safety message was brought to you by Vector Petroleum. Fuel for our futures"- as the computer droned on, O'Donnell rushed over to a computer embedded on the wall. To her horror, the warning on the screen read 'Flooding Initiated. Reactor Malfunction. Emergency Cooling'.

"Oh no" she gasped, "The ghosts tampering with the day-night settings caused a computer malfunction. Its first priority is to keep the reactor cool, so it's opening the hull doors and it's flooding the base".

"Cass says, close the internal flood doors" Lunn instructed, "That'll contain the water in the central corridor".

"The TARDIS is on the other side of the base" Flavia realised, eyes wide, "We need to get back there, now!"

"Okay, we've got thirty seconds before the flood door closes" O'Donnell warned, even as they were sprinting out of the hangar.

/

"Come on!" Clara called to Lunn, who was lagging behind; the Doctor was holding Romana's hand, and the two of them made it across the corridor – so did Bennett and O'Donnell but then…

"Corsair!" Flavia screamed in alarm, as the Time Lord in question dived and scrambled beneath the closing doors. On the other side, he switched on the intercom and said, "Sorry, V, didn't mean to scare you. Sit tight, you lot. We'll come back and get you".

"We can't go straight back, the TARDIS won't go near the ghosts" the Doctor warned.

"What else are we supposed to do?"

"We go back in time" Romana answered, "To when the spaceship landed. If we can understand why this is happening, we can stop them killing anyone else. Look out for each other, all of you, and we'll be back as soon as we can" she told the ones they were leaving behind. She didn't want to leave Emily and Clara, but the Doctor was right, the TARDIS would resist landing near the ghosts and they couldn't risk the TARDIS dematerialising, trapping all of them there.

"Wait, you're going to go back in time?" Bennett asked as they hurried through the corridors, "How do you do that?"

"Extremely well" the Doctor quipped. O'Donnell was struggling not to beam in excitement. Stay focused, stay calm, stay professional. Stay focused, stay calm, stay professional… she told herself over and over as they neared the TARDIS.

/

Cass took charge and led everyone back to the mess hall, to await the return of the others. "You're sure they're not going to hurt us?" Lunn asked nervously, speaking of the ghosts.

"They can't get out of the Faraday Cage" Clara reassured him.

"And my parents will come back for us, so will the Corsair. They won't abandon us" Emily pointed out, sitting on the table and swinging her legs. A look from Flavia, and from Cass made her grin sheepishly and jump off again.

Flavia agreed, "Emily's right; the Corsair is many things, but distrustful, thankfully, isn't one of them. Until then, we just need to be patient and vigilant".

"Are you sure they know what they're doing?" asked Lunn.

"Guys, look, this is how we roll" Clara said confidently, "They're going to go away, come back and we'll have to listen to the Doctor go on and on about how he… did it". She stepped towards the windows, noticing a ghostly figure approaching the Drum from outside, in the flooded village. The other four came to have a closer look as well.

"Is it Moran or Pritchard or the mole guy?" Lunn asked, frowning in bewilderment, "How, how did they get out?"

"No, I…I think it's a different one" replied Flavia, "A different ghost".

"What does that mean?"

"It means something happened in the past, someone else must have…oh no".

"Oh, no, no, no, no" Clara shook her head, horrified, as the figure stopped just outside the window, its blank eyes staring through the glass…the short curled hair, the long coat, the angular face were unmistakable. It can't be, no, no it can't be, not him!

Emily stared at the ghost in horror, mouth open, a few tiny tears prickling the corners of her eyes. "Dad…" she whimpered, shaken. Clara reached for her hand and held it tight. I didn't even get to say goodbye…