And here we go! I thought I'd find it easy to write this one, as it's one of my favourite episodes, but for some reason it was tough. As a result, it ended up being slightly late to post.

But it's here now, so enjoy!

Chapter Twenty: The Fires of Pompeii

Ember landed next in an alley just in time to feel the ground shake ominously. It wasn't too major, but it did make some wicker baskets that were stacked against one wall fall over. The brunette went to one knee and put her hand on the floor, closing her eyes and concentrating.

The quake was natural, but there was something else. It wasn't causing the quake, but it was using it somehow. And it was all coming from one place... one mountain...

"Can you tell me where Foss Street is?"

It wasn't the question itself that brought her out of her concentration, but who was saying it. Ember looked up, and low and behold, the Tenth Doctor was there, talking to a market stall owner who was giving him directions. She stood and walked up to them, just about catching the end of the conversation.

"... then it's the big villa. Can't miss it," The stallholder finished.

"Thanks," the Doctor said. He turned to leave, only to nearly crash into a certain brunette behind him. "Ember!"

The brunette found herself in a hug, which surprised her by making her tense. She'd been somewhat dreading seeing this Doctor again: The last time she'd seen the Tenth Doctor was at The Library, where River had died saving them. It was also where the Doctor had... kissed her...

'No, Ember, focus!' The brunette scolded herself. 'This isn't the time to think about that! Besides, he hasn't been there yet!'

"Ember?" The Doctor's gentle call made her snap out of her thoughts and look at him. He must have noticed that she'd tensed. "Are you alright?"

"Yeah, sorry, was thinking about the last jump. And before you ask, it's in your future so I can't tell you," Ember replied. "Anyway. Shaking town with one mountain. I'm gonna say Pompeii?"

The Doctor blinked and then grinned, taking her left hand and pulling her with him as he walked. "Yeah. Should have known you'd know already. Anyway, we're leaving. This is a-"

"Fixed Point," Ember finished for him, making him glance back at her. "I know. But it's not gonna be that easy to just leave. It wasn't an accident that we're here."

"We really should go."

"We can try."

The Doctor didn't really want to think on that, knowing that it was a hint. He led the brunette back through the streets until he spotted red hair among the crowd, and ran over to none other Donna Noble. "I've got it. Foss Street's this way. And look who I found!"

"Ember!" Donna quickly hugged the brunette before she began to try to pull them in the other direction. "I found this big sort of amphitheatre thing. We can start there. We can gather everyone together. Maybe they've got a great big bell or something we could ring. Have they invented bells yet?"

"What do you want a bell for?" The Doctor asked.

"To warn everyone. Start the evacuation. What time does Vesuvius erupt? When's it due?"

"It's 79AD, twenty third of August, which makes volcano day tomorrow."

"Plenty of time. We could get everyone out easy."

"Yeah, except we're not going to."

Donna paused at that. "But that's what you do. You're the Doctor. You save people."

"Not this time." The Doctor said. "Pompeii is a Fixed Point in history. What happens, happens. There is no stopping it."

"Says who?"

"Says me."

"What, and you're in charge?"

"Tardis, Time Lord, yeah."

"Donna, human, no!" The redhead shot back. "I don't need your permission. I'll tell them myself."

"You stand in the market place announcing the end of the world, they'll just think you're a mad old soothsayer."

"Only because the rest of them won't back you up." Ember put in.

The Doctor ignored the obvious hint, turning to go back the way they'd come. "Now, come on. Tardis. We are getting out of here."

Donna looked furious, but followed. "Well, I might just have something to say about that, Spaceman."

"Oh, I bet you will!"

Ember ran to catch up with the Doctor, taking his hand. "I wouldn't be so sure."

"Please don't try to change my mind." The Doctor said, sounding exhausted by the thought.

"I'm not trying to change your mind. Pompeii is doomed to fall. But what if someone else tries to change that?"

The Doctor didn't know what to make of that, so he decided not to reply. He kept hold of her hand, pulling her with him as he led the way through the streets. Donna was keeping up, but she was fuming.

"Ember, you can't agree with this!" She said as they walked.

Ember bit her lip. "I don't like people dying any more than the next person, but this is history. We can't change it."

"Why not?"

"Because then all those history books in the future will change. Pompeii never gets discovered because it never vanished. Saving a few lives is different because it doesn't make waves: something of this magnitude might cause a disaster."

Donna huffed, letting the matter drop for now but not ready to give up yet.

True to the stallholder's word, they were easily able to find the villa, and they were just reaching the entrance when the ground shook again. The Doctor spotted a marble bust about to fall off its pedestal and ran to it, grabbing it and holding it until the tremor stopped. "Whoa! There you go."

A man looking in his forties approached, his grey hair short, and Ember had to do a double take despite knowing who it was; she had to remember that this man wasn't the Twelth Doctor. "Thank you, kind sir. I'm afraid business is closed for the day. I'm expecting a visitor."

"But that's me, I'm a visitor. Hello!" The Doctor grinned and waved.

"Who are you?"

"I am... Spartacus."

"And so am I." Donna added, getting in on the inside joke.

The man nodded. "Mister and Mrs Spartacus."

"Oh no, no, no. We're not, we're not married." The Doctor said.

Donna shook her head. "We're not together."

"Oh, then brother and sister?" The man assumed. "Yes, of course. You look very much alike."

The Doctor and Donna looked at each other in surprise, speaking at the same time. "Really?"

Ember snorted before she could stop herself, which brought the man's attention to her. "And who might you be, miss?"

"Uh, I am... Gaia." The brunette said the first thing that came to mind. Then she inwardly cursed. Of all the names she could have come up with, it had to be that?

"Oh, is that Greek? A very nice name," The man nodded, not noticing the inner scolding Ember was doing to herself. "I'm sorry, but I'm not open for trade."

The Doctor, who'd glanced back at Ember in surprise at the name she'd chosen, turned to face the man. "And that trade would be...?"

"Marble. Lopus Caecilius." The man finally introduced himself. "Mining, polishing and design thereof. If you want marble, I'm your man."

"That's good. That's good, because I'm the marble inspector." The Doctor flashed the psychic paper at him as well as the wife and son, who were further inside the villa and watching.

The mother gasped. "By the gods of commerce, an inspection." She saw that her son, seated, was holding a goblet of wine and snatched it from him. "I'm sorry, sir. I do apologise for my son."

"Oi!" The son, who Ember recalled was named Quintus or something similar, said as his mother poured the contents of the goblet into the small pond next to them.

"And this is my good wife, Metella." Caecilius said. "I must confess, we're not prepared for a-"

"Nothing to worry about. I'm, I'm sure you've nothing to hide." The Doctor spotted what he was looking for; the familiar tall blue box. "Although, frankly, that object looks rather like wood to me."

"I told you to get rid of it." Metella whispered to her husband as the trio of travellers moved across the room.

"I only bought it today."

The Doctor shrugged. "Ah, well. Caveat emptor."

"Oh, you're Celtic." Caecilius assumed. "That's lovely."

"I'm sure it's fine, but I might have to take it off your hands for a proper inspection."

"Although while we're here," Donna began, "wouldn't you recommend a holiday, Spartacus?"

"Don't know what you mean, Spartacus."

"Oh, this lovely family." Donna gestured to their audience. "Mother and father and son. Don't you think they should get out of town?"

Caecilius blinked. "Why should we do that?"

"Well, the volcano, for starters."

"What?"

"Volcano."

"What ano?"

"That great big volcano right on your doorstep."

The Doctor took Donna by the arm and guided her towards the shrine that had a large, carved plaque of what looked to be gods. "Oh, Spartacus, for shame. We haven't even greeted the household gods yet." He made them stand in front of the plaque as he dipped his fingers in the bowl of water to sprinkle the plaque, lowering his voice so that only the girls could hear him. "They don't know what it is. Vesuvius is just a mountain to them. The top hasn't blown off yet. The Romans haven't even got a word for volcano. Not until tomorrow."

"Oh, great, they can learn a new word as they die." Donna sassed.

"Donna, stop it."

"Listen, I don't know what sort of kids you've been flying round with in outer space, but you're not telling me to shut up. That boy, how old is he, sixteen? And tomorrow he burns to death."

"And that's my fault?"

"Right now, yes."

Suddenly, a servant spoke. "Announcing Lucius Petrus Dextrus, Chief Augur of the City Government."

Another middle-aged man entered the room, wearing a silk cloak that covered the right side of his body. His eyes were cold and calculating.

Caecilius approached the man. "Lucius. My pleasure, as always."

"Quintus, stand up." Metella hissed at her son, who rolled his eyes as he stood.

"A rare and great honour, sir, for you to come to my house." Caecilius held out his hand for Lucius to shake.

Lucius ignored the hand. "The birds are flying north, and the wind is in the west."

Caecilius blinked, thrown by the words. "Quite. Absolutely. That's good, is it?"

"Only the grain of wheat knows where it will grow."

"There now, Metella. Have you ever heard such wisdom?"

"Never. It's an honour." Metella said.

"Pardon me, sir. I have guests. This is Spartacus and, er, Spartacus. And Gaia."

Lucius looked at the trio. "You take the namesake of a goddess? Alas, a name is but a cloud upon a summer wind."

"But the wind is felt most keenly in the dark." The Doctor said in challenge.

"Ah." Lucius tilted his head, accepting the challenge. "But what is the dark, other than an omen of the sun?"

"I concede that every sun must set..."

"Ha!"

"And yet the son of the father must also rise." The Doctor added, nodding to Caecilius and Quintus.

Lucius frowned. "Damn. Very clever, sir. Evidently, a man of learning."

"Oh, yes. But don't mind me. Don't want to disturb the status quo."

"He's Celtic." Caecilius said in explaination of the foreign words.

"We'll be off in a minute."

Donna frowned as he turned toward the Tardis.?"I'm not going."

Caecilius didn't pay them any mind, instead leading Lucius to something that was covered by a sheet. "It's ready, sir."

"You've got to." The Doctor was saying to Donna.

Ember moved to his side and grabbed his arm. "You need to see this."

"The moment of revelation." Caecilius pulled the cloth away. "And here it is."

The Doctor followed Ember's gaze to what had been revealed. It looked like a marble plaque, but the design looked like something that should not be here: a pattern one would find on a circuit board. The brunette saw the spark of interest in his eye and knew he was caught.

Caecilius looked quite proud of the piece. "Exactly as you specified. It pleases you, sir?"

Lucius nodded approvingly. "As the rain pleases the soil."

"Oh, now that's different." The Doctor said. "Who designed that, then?"

"My Lord Lucius was very specific." Caecilus replied.

"Where'd you get the pattern?"

Lucius took this one. "On the rain and mist and wind."

Donna tilted her head. "But that looks like a circuit."

"Made of stone." The Doctor added.

"Do you mean you just dreamt that thing up?"

Lucius answered again. "That is my job, as City Augur."

"What's that, then, like the mayor?"

"Oh, ah... You must excuse my friend, she's from Barcelona." The Doctor turned himself and Donna around so that their backs were facing the audience and lowered his voice. "No, but this is an age of superstition. Of official superstition. The Augur is paid by the city to tell the future. The wind will blow from the west? That's the equivalent of ten o'clock news."

Ember saw her first; a young woman wearing a yellow dress. She looked ill, with red eyes and an unsteady stance. Then she spoke. "They're laughing at us. Those two, they use words like tricksters. They're mocking us."

The Doctor turned, seeing the woman. "No, no, I'm not. I meant no offence."

"I'm sorry." Metella said, walking to the girl's side. "My daughter's been consuming the vapours."

"Oh for gods, Mother. What have you been doing to her?!" Quintus exclaimed at the sight of his sister.

Caecilius tried to calm his son. "Not now, Quintus."

"Yeah, but she's sick. Just look at her!"

Lucius watched the girl carefully. "I gather I have a rival in this household. Another with the gift."

"Oh, she's been promised to the Sibylline Sisterhood." Metella said. "They say she has remarkable visions."

Lucius almost scoffed. "The prophecies of women are limited and dull. Only the menfolk have the capacity for true perception."

"I'll tell you where the wind's blowing right now, mate." Donna said.

Suddenly there was a tremor. Lucius didn't even smirk, but it was obvious that he was smug. "The Mountain God marks your words. I'd be careful, if I were you."

"Consuming the vapours, you say?" The Doctor asked, ignoring the man and addressing the girl.

"They give me strength." Evelina said, though she swayed on the spot.

"It doesn't look like it to me."

"Is that your opinion... as a doctor?"

That made the Doctor pause. "I beg your pardon?"

"Doctor. That's your name."

"How did you know that?"

Evelina looked at Donna next. "And you. You call yourself Noble."

"Now then, Evelina. Don't be rude." Metella tried to quiet her daughter.

"No, no, no, no. Let her talk." The Doctor gently insisted.

Evelina then looked at Ember. "And you... call yourself Ember. You chose the name of the goddess Gaia without knowing why, but it fits you. You bring the fire, and the raging water, and the angry earth... and soon you will call upon the soothing wind..."

The brunette tilted her head, not denying nor confirming the comments.

"All three of you, you come from so far away..."

"The female soothsayer is inclined to invent all sorts of vagaries." Lucius dismissed.

The Doctor shook his head. "Oh, not this time, Lucius. No, I reckon you've been out-soothsayed."

"Is that so... man from Gallifrey?"

"What?" The Doctor looked at the man in shock.

"The strangest of images. Your home is lost in fire, is it not? But not hers."

"Doctor, what are they doing?" Donna asked.

"And you... daughter of London." Lucius said.

"How does he know that?"

"This is the gift of Pompeii. Every single oracle tells the truth."

"That's impossible."

"Doctor... she is returning."

The Doctor furrowed his brow. "Who is? Who's she?"

"And you, daughter of London." Lucius looked at Donna again. "There is something on your back."

Donna put an arm around her back, though she didn't feel anything. "What's that mean?"

Lucius smirked, and then he looked at Ember. "And you... You glimpse the future and are a master of Elements... but at the cost of two. One was taken, the other given, two to become one. None knew what you would become, or what you would do in vengeance..."

That made Ember pause. Cost of two? Vengeance? What did that mean?

"Even the words Doctor and Ember are false." Evelina continued. "Your real names are hidden. One was burned away. The other burns in the stars, in the Cascade of Medusa herself. You are Lords. Lords... of Time..."

With that, the young woman fainted, much to the mother's distress. "Evelina!"

The Doctor ran to help, followed by Donna. Ember glanced over at Lucius, who met her gaze readily. He looked like he didn't trust her, more so than anyone else, but he was taken aback when he saw her pupils become unseen in liquid silver for the briefest instant.

After Lucius had left with his commission, the trio of time travelers split up. Donna has chosen to help Metella with caring for Evelina, while the Doctor and Ember got Caecilius to show them where the daughter had been 'consuming the vapours.'

The Doctor, having taken his trench coat off and put it in the Tardis, pulled off the grill that covered a large hole in the ground that had heat and steam rising from it. "Different sort of hypocaust?"

"Oh, yes." Caecilius said, moving to sit next to the exposed hole. "We're very advanced in Pompeii. In Rome, they're still using the old wood-burning furnaces, but we've got hot springs, leading from Vesuvius itself."

"Who thought of that?"

"The soothsayers, after the great earthquake, seventeen years ago. An awful lot of damage. But we rebuilt."

"Didn't you think of moving away?" The Doctor pulled a face. "Oh no, then again, San Francisco..."

"That's a new restaurant in Naples, isn't it?"

The Doctor was spared from answering that by a loud noise from below, almost like a growl. He also noticed that Ember was tense where she was leaning over from the other side of the hypocaust. "What's that noise?"

"Don't know. Happens all the time." Caecilius said. "They say the gods of the Underworld are stirring."

"But after the earthquake, let me guess... Is that when the soothsayers started making sense?"

"Oh, yes, very much so. I mean, they'd always been, shall we say... imprecise? But then the soothsayers, the augurs, the haruspex, all of them, they saw the truth again and again. It's quite amazing. They can predict crops and rainfall with absolute precision."

Ember bent her arms until her chin was nearly resting on the edge of the hole. She couldn't see anything specific, but she could sense the earth shaking below. Thanks to the natural quaking, it could easily be missed, but she could tell: there were footsteps hidden.

"Haven't they said anything about tomorrow?" The Doctor asked.

"No." Caecilius replied. "Why, should they? Why do you ask?"

"No, no. No reason. I'm just asking. But the soothsayers, they all consume the vapours, yeah?"

"That's how they see."

"Ipso facto." The Doctor ran his hand over the edge of hypocaust after putting his glasses on.

"Look you..."

He was cut off when the Doctor pulled his hand back, rubbing his fingers. They were covered in loose dirt. "They're all consuming this."

Caecilius looked at it himself. "Dust?"

"Tiny particles of rock." He tasted it, which made Ember pull a face. "They're breathing in Vesuvius."

"They're doing more than that," Ember finally spoke, pulling away from the hypocaust and standing up. The two men watched her as she glared at the hole. "There's more down there than rock. And they're not good."

The Doctor stood and moved to her side, taking her hand. Caecilius looked thoughtful for a long moment before he spoke. "I need to work. You are welcome to stay here."

As he turned and left the room, the Doctor turned to Ember. "I have a question for you. Why did you say your name was Gaia?"

"I dunno." Ember shrugged. "It was the first thing that came to my mind. I think that's a goddess's name, but I'm not sure where from."

"Gaia is the Greek goddess of primordial earth. She was said to be the creator of the earth and the universe."

"Hmm." Ember looked away in thought. Why did that name come to mind? "Not sure why I picked it. I'm no goddess."

"Well, you can create fire. That's something a god could do," the Doctor offered as he stepped closer.

Ember looked up at him as he got closer, finding her breath hitching slightly as he took her hands. She recognised that look; it was the one he'd given her before he kissed her. It even looked like he was about to lean down towards her...

Then the ground shook, forcing them out of their moment in order to keep their balance. Ember mentally cursed at the interruption, but she was also slightly greatful; she was getting too close.

'You need to stop it', she thought to herself. 'You'll only get hurt if you keep crushing on him like this!'

The Doctor didn't seem to notice her inner struggle, clearing his throat. "So, any hints?"

"Remember Caecilius' face. It's an important lesson that you need to remember," Ember said, catching him off guard as he looked to where the father had just left. "As for the hypocaust... like I said, there's more in that mountain than rock and lava. And Lucius is involved. Petrus Dextrus: It's more than a name."

The Doctor nodded. "So we talk to Lucius, or we poke around his place."

"You'll get more out of option two. But we don't know where he lives. We could use a guide; someone who isn't happy with the way things are going with their sister."

That was easy to figure out, so the Doctor led Ember back to the main villa, where Quintus was sat on the couch with another goblet of wine in his hand.

"Quintus, me old son." The Doctor said. "This Lucius Petrus Dextrus. Where does he live?"

The boy barely looked up. "It's nothing to do with me."

"Let me try again. This Lucius Petrus Dextrus..." The Doctor reached out and made a motion like he'd pulled a coin from the boy's ear. "Where does he live?"

Ember held back a snicker at the suddenly interested look on Quintus' face.

Night had fallen in Pompeii. The Doctor and Ember followed Quintus through the streets towards another large villa, using a torch to light the way.

Once they got to where Lucius lived, Quintus led them to the side where there was a window. "Don't tell my Dad."

The Doctor did a small run up to get on a barrel below the window and use it to get up to the window, glancing back down at them after opening the shutters. "Only if you don't tell mine." He got inside and then leaned out with a hand. "Pass me that torch."

Ember waited for him to move away from the window before climbing onto the barrel and getting in herself, knowing that Quintus would soon follow. Inside, there was another hypocaust that was larger than the one they'd seen before, and she looked through the grate to see if they were being watched. So far, she couldn't sense any movement below.

The Doctor looked around the room as Quintus climbed through the window, peeking around curtains and drapes until he found something. Handing the boy the torch, he pulled back the drape to reveal several stone plaques that resembled circuit boards.

"The liar." Quintus whispered. "He told my father it was the only one."

The Doctor put on his glasses and examined the plaques. "Well, plenty of marble merchants in this town. Tell them all the same thing, get all the components from different places, so no one can see what you're building."

"Which is what?"

"The future, Doctor." The trio turned to find Lucius entering with room with two guards in armour. "We are building the future, as dictated by the gods."

Ember narrowed her eyes. "How about instead of killing us right away, maybe you can let a man of learning try to figure that out. Because you don't know what order that's supposed to go in. What if you get it wrong?"

Lucius, surprisingly, accepted the offer, nodding to the Doctor. The Time Lord immediately got to work, making Quintus and Ember hold the plaques while he rearranged them.

"Okay... Put this one there. This one there." The Doctor hesitated as he put the last one in place. "Uh, keep that one upside down, and what you got?"

"Enlighten me." Lucius said.

"What, the soothsayer doesn't know?"

"The seed may float on the breeze in any direction."

Ember rolled her eyes. Could this man not just answer in plain English? Or Latin, or whatever language was being translated by the Tardis.

"Yeah, I knew you were going to say that." The Doctor shrugged. "But it's an energy converter."

"An energy converter of what?"

"I don't know. Isn't that brilliant? I love not knowing. Keeps me on my toes." The Doctor then moved to sit on the edge of the table. "It must be awful being a prophet, waking up every morning, 'is it raining? Yes, it is, I said so.' Takes all the fun out of life. But who designed this, Lucius, hmm? Who gave you these instructions?"

"I think you've babbled enough."

"Lucius, really, tell me. Honestly, I'm on your side. I can help."

"You insult the gods." Lucius said. "There can be only one sentence. At arms!"

The guards, who'd moved to the exits to stop them from leaving, drew their short swords.

The Doctor pulled Ember to stand behind him as he and Quintus backed up slightly. "Oh, morituri te salutant."

"Celtic prayers won't help you now."

Quintus looked terrified. "But it was him, sir. He made me do it. Mister Dextrus, please don't!"

"Come on now, Quintus, dignity in death. I respect your victory, Lucius. Shake on it?" The Doctor stuck out his right hand, which Lucius ignored. "Come on. Dying man's wish?"

When there was no verbal response, the Doctor then lunged forward, grabbing the arm that was hidden beneath Lucius' cloak. With one quick jerk and sickening crack that made Lucius cry out, the Doctor pulled the arm away as he stepped back: only to reveal that the limb was solid stone.

Quintus looked at the stone limb in shock. "But he's..."

"Show me." The Doctor said to Lucius.

The man, still scowling, pushed back his cloak to reveal that his right side from the shoulder was stone as well. "The work of the gods."

"He's stone!" Quintus exclaimed.

"Armless enough, though. Whoops!" The Doctor tossed the stone arm back to Lucius, who tried to catch it as the Time Lord pushed Ember towards the window. "Quintus!"

Ember turned and threw out both her hands, one facing the guards and the other towards the stone circuit board. A burst of fire sprung up from the floor in front of the guards to prevent them from advancing, while the ground shook under the plaques, which made them fall to the floor. Using the distraction, Quintus quickly followed the Time Lords out of the window and to the street.

The Doctor led them through the streets until they reached an intersection, stopping so they could regroup. "No sign of them. Nice little bit of allons-y. I think we're all right."

"But his arm, Doctor. Is that what's happening to Evelina?" Quintus asked before he looked at Ember, who was now on one knee with her hands pressed to the floor and her eyes closed. "And you... you brought fire, just like she said..."

"I'll explain later, I promise," Ember said to him, not bothering to look up. She concentrated, feeling the earth beneath them shift, but before she could sense anything else, her head gave a throb and she felt a vision come...

The Doctor tried to talk to the stone giant, but it didn't have any intention on listening. It breathed fire at the Time Lord, incinerating him in seconds...

Ember was brought out of the vision by a low rumble beneath her hands. It was short, but strong, and soon followed by another.

The Doctor looked around. "What was that?"

"The mountain?" Quintis suggested.

"Too rhythmical," Ember said. "And it's too close."

The Doctor looked down a street as dogs began to bark and things started falling over. "She's right. I think it's footsteps..."

"It can't be..." Quintus breathed.

"Footsteps underground."

"What is it? What is it?"

Ember stood and ran to the boys, grabbing them both. "It's after us, that's what it is! Let's go!"

They ran again, flinching as several vents and hypocausts blew as they passed, grills flying off with the pressure.

The rumbling and the blowing grills followed them back to Caecilius' villa, where they found the rest of the family, some servants and Donna looking around.

"Caecilius!" The Doctor called as the trio ran in. "All of you, get out!"

"Doctor, what is it?" Donna asked.

"I think we're being followed." The grill of the nearest hypocaust suddenly flew off as steam rose thickly from it. "Just get out!"

But no one listened, watching in confusion and awe as the ground around the hypocaust began to crack and bulge. Then the whole thing broke apart, forced to give way for a massive creature. It looked humanoid, but stood at about ten feet tall and was made of stone that was seemingly jointed with lava. It looked like it wore a helmet of stone as it turned to look at them with yellow eyes.

"The gods are with us!" Evelina gasped.

The Doctor looked at the pond that was between them and the creature. "Water... We need water. Quintus! All of you, get water! Donna!"

As Quintus and Donna ran off to get buckets, a servant stepped closer to the creature. "Blessed are we to see the gods."

The creature turned to him and inhaled, but before it would breathe fire on the helpless human, Ember suddenly jumped forward, throwing her hand out and making a line of fire spring up between them. It obviously didn't scare the creature, it did prevent it from finishing the attack. Ember then used the chance to grab the servant by the back of his robe and yank him back to the rest of the group.

The Doctor stepped forward as the flames dispersed. "Talk to me! That's all I want. Talk to me. Just tell me you are. Don't hurt these people!"

Ember ran over to stand between him and the creature. "It's not going to listen!" She held her hand out toward the pond and closed her eyes to concentrate, and when she opened them, her pupil and sclera were engulfed in liquid silver. The water from the pond suddenly bubbled and rose up like a snake, like she'd done with the swimming pool in the Tardis. It swirled around until it was between the creature and the Time Lords, facing the creature and rearing up. It even expanded at the top like a cobra would do, a sound that might have been watery hiss coming out.

Caecilius and his family looked on in shock as the Doctor watched Ember closely. Sweat was already breaking out on her forehead as she kept her focus on the water.

Then the 'snake' struck, lunging forward and crashing into the stone giant. The shape was lost as the creature was drenched from head to foot, and it gave a low wail as the magma in its body was suddenly cooled and solidified. It became still for a second before it broke apart, falling to the ground in a pile of rocks and dust. By this time, Quintus had returned with a bucket and was now looking on the rest of the humans at the unbelievable event they'd just witnessed.

Ember dropped her hand, and then promptly collapsed. She'd have hit the floor if the Doctor hadn't been quick to catch her. She tiredly looked up at him as he held her, her back against his chest.

"What was that?" Caecilius asked after a moment of quiet.

"Carapace of stone, held together by internal magma." The Doctor replied. "Not too difficult to stop, but I reckon that's just the foot soldier."

"I meant the water! How did she do that? It was like she summoned a serpent..."

"Doctor, or whatever your name is," Metella said, "you bring bad luck on this house."

The Doctor glanced over at the family. "I thought your son was brilliant. Aren't you going to thank him?" He turned his attention back on the brunette in his arms. "Hey... you alright there?"

"Yeah..." Ember slowly got back to her feet, the Doctor letting her use him to steady herself. "Okay, that wasn't as bad as I thought it'd be..."

"You are Gaia..."

Ember turned at the quiet voice. Evelina was looking at her like she'd just performed a miracle. "I'm really not, you know..."

"But you called a serpent of the water..." the young woman said. "I... should never have doubted you..."

"Um..." Ember didn't know what to say about that. Luckily, she didn't have to, as she realised who was missing. "Oh... Doctor? Donna's gone."

The Doctor looked around. "Donna? Donna! Where'd she go?"

"Not here, Doctor." Ember said before turning to Evelina again. "Okay, I know you saw them take her. If you want to make it up to us, just tell us where the temple is. Please."

Evelina looked surprised that she'd been caught, but she was more than willing to give them what she was asked.

After getting directions to where Donna had been taken, the Doctor and Ember made their way to the temple of the Sibyl. They were quiet as they snuck in and reached the main chamber.

There were several women in red robes at the foot of the steps that led up to an curtained off area. There was also a large, flat altar where Donna was tied to the slab. She was wearing a purple toga that she'd borrowed from Evelina.

"Listen, sister, you might have eyes on the back of your hands, but you'll have eyes in the back of your head by the time I've finished with you!" Donna was saying. "Let me go!"

The leader of the women, who was standing next to the altar, raised a large blade above her head. "This prattling voice will cease forever!"

"Oh, that'll be the day." The Doctor said, having moved to lean against one of the pillars. Ember was leaning against the other side. Everyone looked at them in surprise.

"No man is allowed to enter the Temple of Sibyl." The woman with the knife said.

The Doctor usher away from the pillar with a shrug. "Well, that's all right. Just us girls. Do you know, I met the Sibyl once. Yeah, hell of a woman. Blimey, she could dance the Tarantella. Nice teeth. Truth be told, I think she had a bit of a thing for me. I said it would never last. She said 'I know'. Well, she would." He reached the altar and looked down at Donna. "You all right there?"

"Oh, never better."

"I like the toga."

"Thank you. And the ropes?"

"Yeah, not so much." With a flick of his Sonic, the ropes came undone.

The woman with the knife looked surprised. "What magic is this?"

Ember tilted her head. "You must have seen what I can do, right, Spurrina?"

That made the woman turn to look at her in shock. "How did you know my name?"

"I know a lot more than that."

The Doctor spoke, getting the attention back on himself. "Let me tell you about the Sibyl, the founder of this religion. She would be ashamed of you. All her wisdom and insight turned sour. Is that how you spread the word, hey? On the blade of a knife?"

"Yes, a knife that now welcomes you!" Spurrina raised her blade again, but was interrupted.

"Show me this man and woman." A grating voice that barely identified as being female spoke from behind the veil at the top of the steps.

Spurinna turned in an instant, the other women going to their knees and bowing low. "High Priestess, the strangers would defile us!"

"Let me see. These two are different. They carry starlight in their wake."

The Doctor approached the steps. "Oh, very perceptive. Where do these words of wisdom come from?"

A form could just about be seen through the veil: a humanoid sitting up on what appeared to be a bed. "The gods whisper to me."

"They've done far more than that. Might I beg audience? Look upon the High Priestess?"

Two of the women went up the steps and pulled the veil aside. On the bed that was revealed was another woman in red robes, but her body looked like dry and crusted earth.

"Oh, my God!" Donna gasped. "What's happened to you?"

"The heavens have blessed me." The High Priestess wheezed.

The Doctor held out his hand. "If I might...?" He approached and gently took her arm when she offered it to him, examining the skin. "Does it hurt?"

"It is necessary."

"Who told you that?"

"The voices."

"Is that what's going to happen to Evelina?" Donna asked before she looked at the other women. "Is this what's going to happen to all of you?"

Spurinna stepped forward and pulled back her sleeve, revealing that her forearm was grey and solid. "The blessings are manifold."

Donna reached out to touch it. "They're stone."

The Doctor nodded. "Exactly. The people of Pompeii are turning to stone before the volcano erupts. But why?"

"This word, this image in your mind." The High Priestess said. "This volcano. What is that?"

"More to the point, why don't you know about it? Who are you?"

"High Priestess of the Sibylline-"

"No, no, no, no." The Doctor cut her off. "I'm talking to the creature inside you. The thing that's seeding itself into a human body, in the dust, in the lungs, taking over the flesh and turning it into... what?"

"Your knowledge is impossible." The High Priestess looked at Ember, which made the brunette tense. "And you... who calls upon fire and summons serpents of water... you are impossible..."

The Doctor spoke before Ember could. "Oh, but you can read our minds. You know it's not. I demand you tell me who you are."

When the High Priestess spoke again, it was with two voices; her own and a much deeper one that definitely wasn't human. "We... are... awakening!"

"The voice of the gods!" Spurinna gasped.

Her sisters sat up on their knees and began rocking while chanting "Words of wisdom, words of power. Words of wisdom, words of power. Words of wisdom..."

The Doctor didn't acknowledge them, keeping his attention on the High Priestess as she slowly climbed off the bed. "Name yourself! Planet of origin, galactic coordinates, species designation according to the universal ratification of the Shadow Proclamation!"

"We are... rising!"

"TELL ME YOUR NAME!"

"Pyrovile!"

The sister's chanting changed. "Pyrovile. Pyrovile. Pyrovile..."

"What's a Pyrovile?" Donna asked.

The Doctor nodded at the High Priestess. "Well, that's a Pyrovile, growing inside her. She's a halfway stage."

"What, and that turns into...?"

"That thing in the villa. That was an adult Pyrovile."

"And the breath of a Pyrovile will incinerate you, Doctor!" The High Priestess exclaimed.

Ember moved forward at that. "It'll have to get past me first, and I'm a lot harder to burn."

The Doctor took out a yellow water pistol from his pocket. "I warn you, I'm armed. Donna, get that grill open."

Donna looked at the grill. "What for?"

"Just..." The Doctor gestured with his head before focusing on the High Priestess. "What are the Pyrovile doing here?"

"We fell from the heavens. We fell so far and so fast, we were rendered into dust."

"Right, creatures of stone shattered on impact. When was that, seventeen years ago?"

"We have slept beneath for thousands of years."

"Okay, so seventeen years ago woke you up, and now you're using human bodies to reconstitute yourselves. But why the psychic powers?"

"We opened their minds and found such gifts."

"Okay, that's fine." The Doctor was getting impatient. "So you force yourself inside a human brain, use the latent psychic talent to bond. I get that, I get that, yeah. But seeing the future? That is way beyond psychic. You can see through time. Where does the gift of prophecy come from?"

"Got it!" Donna called, finally getting the grill off the hypocaust.

The Doctor backed up, making sure Ember was with him. "Now get down."

"What, down there?"

"Yes, down there!" The Doctor shot back before facing the women again. "Why can't this lot predict a volcano? Why is it being hidden?"

The High Priestess looked at Ember. "Why not ask her? She has seen our futures like stories. Does she not know?"

"I know what's supposed to happen and what shouldn't," the brunette replied. "And I'll tell you now, what you're doing won't happen."

"Sisters, I see into his mind!" Spurinna suddenly cried. "The weapon is harmless!"

"Yeah, but it's got to sting." The Doctor used the pistol, squirting water at the High Priestess. She recoiled in pain as the water sizzled on her skin, nowhere near damaging but enough to give the Doctor time to grab Ember by the hand and lead her to the open hypocaust as the sisters ran to help their leader. "Get down there!"

"You first! I'm fireproof!" Ember insisted, and then Doctor reluctantly complied. Before the brunette followed, though, she turned to the sisters, locking eyes with Spurrina. "This is your last chance: Get out of Pompeii while it's still standing. If you don't, you will all burn."

With that, she put her feet into the hypocaust and jumped down into it, landing in a narrow passageway. She was lucky not to land on the Doctor, who'd been waiting for her.

The Doctor took her hand and pulled her with him along the passage. "This way!"

"Where are we going now?" Donna asked.

"Into the volcano."

"No way!"

"Yes, way! Appian way!"

Donna followed them through the hot tunnels, and then a thought struck her. "But if it's aliens setting off the volcano, doesn't that make it all right for you to stop it?"

The Doctor shook his head. "Still part of history."

"But I'm history to you. You saved me in 2008. You saved us all. Why is that different?"

"Some things are fixed, some things are in flux. Pompeii is fixed."

"Donna, please leave it," Ember tried to warn her, but she didn't listen.

"How do you know which is which?"

The Doctor stopped, turning to the woman. "Because that's how I see the universe. Every waking second, I can see what is, what was, what could be, what must not. That's the burden of a Time Lord, Donna. And Ember and I are the only ones left."

"Is that how you see it?" Donna asked Ember.

"Kind of." The brunette admitted. "It hurts my head when something disrupts the timeline too much. And that's best case scenario: you haven't met the Reapers, and you don't want to."

For a moment it looked like Donna was going to drop it, but then she looked at the Doctor. "How many people died?"

"Stop it." He warned.

"Doctor, how many people died?"

"Twenty thousand."

"Is that what you can see, Doctor? All twenty thousand? And you think that's all right, do you?"

Ember moved to stand between the pair, her eyes narrowed. "It's not a matter of what's right or wrong. Sometimes... bad things have to happen. We just don't have to like it."

There was a low roar from the passage they'd come from. The Doctor backtracked and took the two women by the hands. "They know we're here. Come on."

The trio ran on, climbing over rocks and avoiding plumes of fire and pools of lava, until they arrived at a massive carvern or crater. They carefully looked over a large rock to see several large, stone creatures walking around.

"It's the heart of Vesuvius." The Doctor said. "We're right inside the mountain."

"There's tons of them." Donna said, eyeing the creatures.

Ember pat the Doctor on the arm and pointed to something. Squinting, the Doctor got a monocular out of his pocket to get a better look. It looked like a boulder, but it had a door in the side. "What's that thing?"

"Oh, you better hurry up and think of something." Donna said, hearing footsteps behind them. "Rocky Fall's on its way."

"That's how they arrived. Or what's left of it. Escape pod? Prison ship? Gene bank?"

"But why do they need a volcano? Maybe it erupts, and they launch themselves back into space or something?"

"If it was that easy, I'd have made us leave by now." Ember said. "But it's worse than that."

"How could it be worse?" Another rumble came from behind them. "Doctor, it's getting closer."

"Heathens defile us!" A voice yelled. The trio looked to where Lucius was standing on a ridge. From his vantage point, he was able to see them easily. "They would desecrate your temple, my lord gods!"

The Doctor couldn't see any other way out, so he led the girls towards the pod in the centre of the cavern. "Come on!"

Donna was quick to catch on. "We can't go in!"

"Well, we can't go back!"

Crush them!" Lucius yelled. "Burn them!"

A Pyrovile reared up in front of the trio, but Ember was quick to make a line of flames appear so that they could get around it and reach the pod.

"There is nowhere to run, Doctor, and daughter of London, and bringer of fire." Lucius said.

The Doctor turned and faced them. "Now then, Lucius. My lords Pyrovillian, don't get yourselves in a lather. In a lava?" He looked at the ladies. "No? No. But if I might beg the wisdom of the gods before we perish. Once this new race of creatures is complete, then what?"

"My masters will follow the example of Rome itself. An almighty empire, bestriding the whole of civilisation."

"But if you've crashed, and you've got all this technology, why don't you just go home?" Donna called.

"The Heaven of Pyrovillia is gone."

The Doctor frowned. "What do you mean, gone? Where's it gone?"

"It was taken. Pyrovillia is lost. But there is heat enough in this world for a new species to rise."

"Yeah, I should warn you, it's seventy percent water out there."

"Water can boil." Lucius said. "And everything will burn, Doctor."

"Then the whole planet is at stake. Thank you. That's all I needed to know. Donna, Ember." The Doctor ushered the girls into the pod, closing the door with his Sonic. Inside, it was a little cramped, what with the small space and the marble circuit board that had been put in.

"Could we be any more trapped?" Donna said, then flinched as the temperature suddenly increased, more so than it already was. "Little bit hot."

Ember put her hands on either side of the walls, closing her eyes and concentrating. The temperature didn't raise any more, though it was already like a sauna. "I can keep the heat out, but I dunno for how long! This is the first time I'm doing this!"

The Doctor was quick to examine the control panel that the circuit boards were attached to. "See? The energy converter takes the lava, uses the power to create a fusion matrix, which welds Pyrovile to human. Now it's complete, they can convert millions."

"But can't you change it with these controls?" Donna asked.

"Of course I can, but don't you see? That's why the soothsayers can't see the volcano. There is no volcano! Vesuvius is never going to erupt. The Pyrovile are stealing all its power. They're going to use it to take over the world."

"But you can change it back?"

"I can invert the system, set off the volcano, and blow them up, yes. But, that's the choice, Donna. It's Pompeii or the world."

Donna finally figured out what that meant. "Oh, my God."

"If Pompeii is destroyed then it's not just history... it's me." The Doctor breathed. "I make it happen."

"Hate to rush you, but this ain't getting any easier!" Ember called.

Donna leaned over the Doctor's shoulder. "Doctor, the Pyrovile are made of rocks. Maybe they can't be blown up."

"Vesuvius explodes with the force of twenty four nuclear bombs. Nothing can survive it. Certainly not us."

"...Never mind us."

The Doctor put his hands on a large stone lever, though they were trembling. "Push this lever and it's over. Twenty thousand people..."

Donna slowly put her hands over his on the lever. Just before she urged them to push, a third pair covered their hands, feeling very hot. They both looked up to see that Ember had joined them. With one unified nod, the trio pushed the lever down.

The result was almost instant: there was a massive explosion from outside, and the whole place shook. Ember probably would have been flung at a wall if it weren't for the Doctor holding her to his own body.

Then there was one last thud, and everything stilled. Donna, who was closest to the door, pushed it slightly and it fell away, revealing that they'd landed just outside of town.

"It was an escape pod." The Doctor said.

Ember looked back at the mountain, seeing the avalanche of ash barrelling down from the top, which was spewing lava and rocks. "We need to go. Now!"

The trio ran, miraculously staying ahead of the worst of the fallout as the smoke and ash from the eruption blocked out the sunlight. They reached the town, the residents running in panic as ash was falling like snow around them.

"Don't go to the beach!" Donna was yelling to anyone they passed. "Don't go to the beach, go to the hills! Listen to me! Don't go to the beach, it's not safe!" She saw a young boy crying alone and went to comfort him. "Come here..."

A woman, hopefully the mother, appeared and picked up the boy. "Give him to me!"

Ember stepped in front of her, grabbing her arm and meeting her gaze as her eyes flashed silver. "Go to the hills if you want to live."

The woman, though scared, saw something in those silver eyes that made her listen, and she nodded before running off with her child. Ember turned to take Donna's hand and catch up with the Doctor, who was waiting for them before they all ran to the villa where the Tardis was parked.

Inside the villa, Caecilius, Metella, Quintus and Evelina were huddled together, scared. The father saw the trio run in and held out his hand. "Gods save us, Doctor!"

The Doctor paused for only a moment before he ran to the Tardis, unlocking the door and going inside.

"No! Doctor, you can't..." Donna said, running after him. "Doctor!"

"Gaia!" Ember turned at the call, to see Evelina looking at her. "Please, Gaia! Have mercy!"

Ember ran over to them and knelt. "Pray. For the next ten seconds, pray. And we will answer."

She then stood and ran into the Tardis, closing the door just before the blue box disappeared from the villa. Inside, Donna was yelling at the Doctor.

"You've got to go back! Doctor, I am telling you, take this thing back! It's not fair!"

"No, it's not." The Doctor agreed, though he made no attempt to backtrack.

"But your own planet... It burned."

"That's just it. Don't you see, Donna? Can't you understand? If I could go back and save them, then I would. But I can't. I can never go back. I can't. I just can't... I can't..."

Donna was openly weeping and not caring who saw. "Just someone... Please... Not the whole town. Just save someone."

The Doctor was about to reply when the Tardis suddenly lurched. He looked at the other side of the console and saw Ember doing something on the control panel. "What are you doing?"

"Stopping you from making a big mistake!" She said, not looking at either of them as she flipped a switch. "The town of Pompeii has to fall, and twenty thousand people die. But there are more than twenty thousand people in the town, isn't there?" She finally met the Doctor's gaze. "You can't always save everyone. But sometimes, you can save one family."

The Doctor stared at her for a moment, and then he nodded, moving to help her. Ember made sure they landed exactly ten seconds after they'd left, and then the Doctor ran to the doors and opened it to look at the family still huddled together.

He held out his hand. "Come with me."

Caecilius reaches out, taking the offered hand.

On a hill overlooking Pompeii, the Doctor, Ember, Donna and the family looked on as their home was engulfed in volcanic ash.

"It's never forgotten, Caecilius." The Doctor said after a few moments. "Oh, time will pass, men'll move on, and stories will fade. But one day, Pompeii will be found again. In thousands of years. And everyone will remember you."

"What about you, Evelina?" Donna asked. "Can you see anything?"

Evelina closed her eyes. "The visions have gone."

"The explosion was so powerful it cracked open a rift in time, just for a second." The Doctor explained. "That's what gave you the gift of prophecy. It echoed back into the Pyrovillian alternative. But not any more. You're free."

Metella shock her head. "But tell me. Who are you, Doctor? With your words, and your temple containing such size within?"

"Oh, I was never here. Don't tell anyone."

Evelina turned to Ember. "Thank you for saving us, Gaia."

"My friends call me Ember," the brunette said with a shrug. "You can call me that too."

"The great god Vulcan must be enraged." Caecilius said, looking at the town as it slowly vanished under the ash. "It's so volcanic. It's like some sort of volcano. All those people..."

The family huddled together to grieve, allowing the travelling trio to sneak into the Tardis and leave.

Donna smiled at the Doctor. "Thank you."

"Yeah." The Doctor replied. "You were right. Sometimes I need someone. Welcome aboard."

Ember smiled. "You're gonna love it."

Six months later, as the family from Pompeii settled into their new lives in Rome, they would give thanks every day to their household gods: depicted by a stone carving of a woman with serpents of fire and water flanking her and a familiar box...

And there we have it! It's a bit later in the day than I wanted, but I still got it up on a Monday! Let me know what you think, and feel free to ask questions! I'll add my replies in the next chapter.

Next Time: Ember drops in on another companion's first meeting with the Doctor. But which one? Stay tuned to find out!