~Tech block~

"I've found a secret room", Luke said as Maria and Clyde ran up to him, having just managed to escape Carl, who turned out to be a small Slitheen.

"Not now!" Maria said more interested in getting out of the building. They rushed to the main doors but they wouldn't open.

"That thing's real, isn't it?" Luke asked.

"It's real", Clyde confirmed.

"This place is sealed. You're finished, right here, right now", Carl's voice called.

"This way", Maria said and she ran, darting past Carl. Unfortunately Luke and Clyde aren't so lucky. They turn and raced up the stairs, Carl chasing after them.

Outside the building Jenna screeched her car to a stop. She tried the doors "locked", she muttered. The brunette smacked her forehead when she remembered she had a sonic screwdriver. She pulled it out of her pocket and flashed it over the lock, yanking the door open. She did the same for the second set of doors and rushed inside. Jenna's eyes widened when she saw Luke and an unfamiliar boy cornered by two Slitheen on the upper level.

She frantically looked around for something she could use as she'd forgotten to grab the vinegar in her haste. Jenna's eyes lit up when she spotted the fire extinguisher. She darted over to it and snatched it up. She ran over to the stairs and crept quietly up them, pulling the pin out as she went.

Jenna stopped near the top and readied the fire extinguisher "Hey ugly!" she called. As expected the Slitheen turned around and she blasted them with CO₂. "Run!" Jenna shouted at the boys.

Luke and Clyde ran past the two Slitheen and headed down the stairs. Jenna lobbed the fire extinguisher as the Slitheen and raced down the stairs. She, Luke and Clyde arrived at the main doors at the same time as Maria did.

Jenna ushered the 3 teens out of the building and soniced the doors shut. She glared at the two Slitheen as they appeared at the door with the headmaster.

"What was that?" Clyde asked as Jenna pocketed her sonic.

"Sonic screwdriver", Luke replied.

"Oh, of course", Clyde said as if that explained everything. The four got in the car and Jenna drove off.

"You want to tell me who that is you two?" Jenna asked glancing in the rear-view mirror at Clyde.

"I'm Clyde. Clyde Langer", Clyde spoke up.

"Oh, you're Clyde. When this is over, you and I are going to have a little chat about how you treat my brother", Jenna said in a tone which told Clyde there was no way he was getting out of it. "Now, what were you 3 doing at the tech block?"

"Sarah Jane asked us to check it out", Maria replied.

"Luke you better call her up and tell her what happened", Jenna said. Luke nodded, got his phone for out from his pocket and called up Sarah Jane.

~Outside number 13~

Jenna pulled up and got out of the car. She and Luke headed inside the house without a word to Maria or Clyde.

"I want answers", Clyde demanded "I've just been chased by aliens and you aren't even freaking out. Why? Who are you?"

"You've got to go home", Maria said firmly "Forget this ever happened. Go home".

"No, I'm part of this now. I want to find out the truth", Clyde continued.

"Just leave us alone, okay?" Maria ordered. They had more important things to deal with than answering Clyde's questions.

"The police won't leave you alone when call them and tell them what happened", Clyde threatened "Show me".

Maria sighed "Ok".

~Attic~

"Luke I'm really sorry I didn't say anything to you or mum", Jenna said apologetically "I should have done. It was stupid of me to keep quiet".

"Jenna, its ok. I don't blame you for not saying anything to us", Luke said.

"But if I had, you would have been prepared. You were nearly killed today because of me", the brunette argued.

"I'm not sure anything could've prepared us for seeing those things", Luke said "and anyway you saved us".

"Yeah I did", Jenna agreed "and I suppose now you've seen the Slitheen…"

"Is that what those aliens are?" Luke asked.

Jenna nodded "yes. And now you've seen them, it's only fair that I tell you all I can about them". She and Luke sat down on the wooden steps "The Slitheen are a family of scavengers from Raxacoricofallapatorius. The first time I met them they'd gotten into Downing Street by impersonating people of importance. They were trying to destroy the Earth by creating World War Three".

"How did you stop them?" Luke asked.

"We blew them up with a missile. Well… I say we, it was Mickey who'd done it but it was the Doctor's crazy plan", Jenna explained "of course this time around…." she was interrupted when Maria and Clyde entered.

"Right, what's going on in here?" Clyde asked.

"Why did you bring him up here Maria?" Jenna asked standing up.

"He was pretty insistent on wanting to find out the truth", Maria replied "and if he tells anyone, who's going to believe him?"

"Whoa, wait. I've just had monsters from outer space on my back and no one's going to tell me what's going on", Clyde said looking between Jenna, Luke and Maria.

"Clyde, shush. We have more important things to do than bringing you up to speed", Jenna said harshly. "Right, Slitheen are in your school and they're responsible for the new building built by Coldfire Construction", she said getting back to the matter at hand "So I'm going to assume they've taken over organisation and that they've put new buildings up in just more than your school and St Cheldons. But why?"

"I think know" Luke said "There's a hidden room in the school. I saw inside".

Maria opened her mouth to say something when they all heard Sarah Jane's voice. "Luke! Jen!"

"We're up here mum!" Jenna shouted. They all heard Sarah Jane run up the stairs and enter the attic.

"Thank goodness you're all right", Sarah Jane said relieved to see them all in one piece. She hugged Luke, Jenna and even Maria. "And you must be Clyde", she said turning to the boy.

"I am", Clyde confirmed.

"Nice to meet you. Now go home", Sarah Jane said. Clyde was a little taken aback by her tone.

"Mum, the aliens are Slitheen", Jenna told her "I think they've taken over Coldfire".

"They have. I had a run in with the one that was posted there", Sarah Jane said.

"Oh god. Are you all right?" Jenna asked.

"Yes, I'm fine", Sarah Jane assured her.

"Luke was just about to tell us what was in the hidden room he'd found at the school", Maria spoke up.

"I've got a theory. Mr Smith could help", Luke said.

"Who's that, your dad?" Clyde asked. Everyone just ignored him.

"Mr Smith, I need you", Sarah Jane said turning to the fireplace where the computer was housed. Clyde stared in disbelief as the fireplace opened up.

"Good afternoon, Sarah Jane", Mr Smith said in his usual polite tone.

"Oh, yes" Clyde grinned "Is that a computer?"

"Who's that?" Mr Smith asked.

"Nobody", Sarah Jane said "Mr Smith, Luke would like some help".

"Certainly. Hello, Luke"

Luke stepped up "Hello, Mr Smith", he said "Bring up our satellite image of London. Now plot the exact positions of every school put up by Coldfire Construction. Ealing, that's us" he pointed to a section on the satellite image.

"St Cheldon's Comp, Upminster. Schools at Epping, Amersham, Richmond, Morden…" Sarah Jane listed off as they appeared.

"The ends of tube lines", Clyde said "If I'm allowed to speak", he added with a bit of sarcasm "This is real. All of it's real. The talking computer's real, the Slitheens are real. Oh, yes". Again everyone just ignored him.

"Mr Smith, plot the position of every Coldfire building put up in the last eighteen months in the world", Sarah Jane instructed.

"Accessing"

"Paris…Sydney…Beijing", Sarah Jane frowned "They're not all capital cities, they're spread out all over the place. They look pretty random".

Jenna eyes widened "railways", she breathed "They've all got underground railways".

"You're right Jenna", Sarah Jane agreed "Link them".

"London, Barcelona, Washington DC, Santiago, Los Angeles, Sydney, Beijing, Moscow, Naples, Paris", Mr Smith listed off as he linked them up with a red line.

"It's like a chain", Jenna murmured "and each site is a link".

"There's at least one Slitheen at every site", Luke stated.

"And there are ten cities. Ten sites", Clyde added "Right, call the army".

"Oh right, because that always makes things better, doesn't it", Maria said turning to him.

"It's not your job", Clyde retorted.

"There's a cleverer way of going about things", Sarah Jane stated "But what's it all for? What are they doing?" she turned to Jenna "any 'feelings'?"

Jenna shook her head "I'm afraid not. The only one I had told me Maria was in danger", she said.

Sarah Jane nodded. She understood that Jenna got those things at seemingly random times. Sometimes she gets a few of them and other times she gets quite a lot. "The secret room, what was in there?" Sarah Jane asked Luke.

"Sarah Jane…Jenna… I've done something really stupid" Luke said, his eyes widening when he realised what he'd done "a really bad social mistake" he turned to face them "I told the Slitheen how to destroy the world".

"It wasn't working until I gave them the answers", Luke said finishing his explanation.

"Oh, Luke", Sarah Jane sighed. She didn't blame him at all. He'd sincerely thought he was helping at teacher out with a theoretical model.

"The power cut last night was a test run", Jenna said remembering how everything lost power, including both the sonic screwdriver and the sonic lipstick. Even Sarah Jane's watch didn't work and that never lost power.

"But our candles went out and that's not electric", Maria pointed out.

"When the capacitors are charged up they act as transducers, converting heat and light into electrical energy. That's how the loop works, it's not connected physically", Mr Smith explained.

"But what has underground railways got to do with that?" Maria asked.

"The system must generate enormous heat. The underground railways must act as a cooling system", Jenna guessed.

"Oh, I'm glad we sorted that out", Clyde said. Jenna was really getting quite annoyed with his remarks. It was just like Kelsey all over again.

"People getting ill, food going off, that's the effect of living or working next to the capacitors", Sarah Jane stated.

"Indeed", Mr Smith agreed "Even on standby, the transducers would cause cellular decay in organic matter".

"With this system they can drain every last drop of energy from the Earth", Luke began.

"And your school is the last link in the chain", Jenna finished.

"But it needs the whole chain all together to do that?" Maria asked.

"Yeah", Luke replied.

"We bomb the school?" Clyde asked hopeful.

"If we could get in there, could you destroy the power system safely?" Sarah Jane asked Luke, ignoring Clyde.

"I think so", Luke answered "If we reset the system, shut it down for just a second. I'd need a cutting tool".

"What about this?" Jenna asked with a smile holding up her sonic.

"Yeah, and how do we get past the Slitheen?" Maria questioned.

"We bomb them?" Clyde asked and Jenna rolled her eyes.

"Clyde if you can't make any useful suggestions, don't say anything at all", Jenna suggested "better yet, why don't you just go home?"

"Sarah Jane, Jenna, I've just picked up this report on an American news channel", Mr Smith spoke up gaining the attention of mother and daughter.

"Breaking news. There's a massive loss of power on the west coast of North America. Los Angeles has gone dark"

"It's starting", Sarah Jane breathed staring at the large screen.

"And I told them how to do it. The day I was born I saved the world. Now I've helped to destroy it", Luke said. Jenna put a comforting hand on your shoulder.

"Anybody could have made that mistake Luke", she said softly.

"No, only he could", Clyde said.

"Clyde!" Maria cried.

"Well, duh. Let's have a High School Musical moment. A group hug'll sort everything out", Clyde said, sarcastically.

"You're going to right way for a slap", Jenna warned giving him a look.

"And the power loss is spreading westwards. China is now without power, and it may be only a matter of time before the effect spreads here. Oh…"

The news report abruptly cut off.

"I have lost the signal", Mr Smith reported.

"We need to find out everything we can on the Slitheen", Sarah Jane stated "specifically their weaknesses".

"I know that one", Jenna said. She crossed the room to the doorway where she'd dumped her shopping bags and pulled out a bottle of vinegar.

"Vinegar?" Clyde asked with a raised eyebrow.

"Yep", Jenna said popping the p "throw this at a Slitheen and say bye" she tossed the bottle up into the air and caught it "I've also got these too", she added producing plastic spray bottles.

"Brilliant Jen!" Sarah Jane cheered.

"Well…" Jenna drawled mimicking the Doctor, getting a laugh from her mother. Suddenly the power went out.

"That's gonna complicate things", Sarah Jane remarked. They needed the sonic screwdriver and or lipstick to gain access to the machinery to reset it.

"It's real. The end of the world, thanks to him", Clyde said giving Luke a look.

"Will you shut up", Maria snapped.

"We can still stop the Slitheen", Jenna said firmly. Just because the sonics weren't working didn't mean she was going to give up. "Empty the vinegar into these bottles", she instructed dumping out the contents of her shopping bags out onto the floor.

"The car's not going to start. How do we get back to school?" Maria asked as they poured the vinegar into the bottles.

"We run", Jenna said with a grin.

As soon as all the vinegar was put into the bottles, the group left the house and started to run.

"Right, so all this fighting aliens stuff, you've been doing it for years?" Clyde asked "is it like…a family business?"

"Not now, Clyde", Jenna waved him off.

"What, did you actually go up to the career guy at school and say, I want to defend the planet from alien invaders?" Clyde continued.

"Not exactly", Sarah Jane said.

"What happened? How did it start?" the boy asked.

"It's a long story. If we survive, I'll be happy to tell you", Sarah Jane said quickly. The five of them stopped when it started going dark. They glanced up at the sun and saw it had turned blue.

"What's going on? Clyde asked.

"It's transduction, like the candles", Luke explained.

"They've switched off the sun!" Maria exclaimed.

"Prisoner zero will vacate the human residence", Jenna muttered under her breath as she stared up the sun. No one else had heard her otherwise they would have given her puzzled looks.

"They're draining its power", Sarah Jane added.

"It's getting cold", Maria shivered.

"We've got about thirty two and a half minutes", Luke informed them.

"Everyone's gonna die!" Clyde exclaimed.

"No they won't Clyde", Jenna said "WE will stop them".

"What, the 5 of us with vinegar in plastic squeezies?" Clyde asked her.

"Yes, the 5 of us with vinegar in plastic squeezies", Jenna repeated "now, Allonsy!" she cried and started to run again. Sarah Jane, Maria, Clyde and Luke chased after her.

~Control room~

Carl spots the group on the CCTV outside the Tech block. "Daddy, that evil girl has come back!" he cried.

"So what? She's just a child with a funny screwdriver. And she won't be able to best us the same way again, my boy", Blakeman assured him.

"My hunt!" Carl hopped up and down.

Blakeman shook his head "I think an adult'd better deal with them this time", he said before reaching up to his forehead and unzipped it.

~Tech block~

"They just let us walk in here", Clyde remarked as both sets of double doors opened easily.

"They want us here", Luke added.

"Well that's considerate of them as we want to be in here", Jenna said cheerfully.

"The secret room?" Sarah Jane asked turning to Luke.

"It's this way", Luke said. They started off in the direction he pointed but stopped when Blakeman spoke up.

"Oh, human children" they all turned and saw him standing there in his Slitheen form "The stench of Haribo and chicken nuggets".

"Get off this planet", Sarah Jane demanded pushing Maria, Luke and Clyde behind herself and Jenna.

"Hush now. It's time to hunt", he said walking towards them "The hunt is an instinct with us. The only way to keep our food safe in the days when the Baaraddelskelliumfatrexius beasts wandered the plains of Raxacoricofallapatorius".

"The what?" Clyde asked.

"They're kind of like giant squirrels", Jenna replied.

"Oh, you are a smart one aren't you?" Blakeman commented "We killed them all centuries ago, but the hunting instinct remains", he explained before he lunged at them.

"Now!" Sarah Jane shouted. Maria stepped out from behind Jenna and sprayed Blakeman. Clyde did the same causing Blakeman to stumble back.

"Didn't like that, did you?" Clyde asked.

"Vinegar. Get back", Maria warned.

"Sarah Jane, Jenna this way", Luke said.

"Maria?" Jenna said as Luke led Sarah Jane away.

"It's working. We're doing our bit, you do yours", Maria said not taking her eyes off Blakeman.

"Ok", Jenna said. She pulled out the plastic spray bottle of vinegar from her shoulder bag and set it down by the wall. She then hurried after her mother and brother.

Jenna managed to catch up to them as Luke and Sarah Jane reached the wall where the entrance to the secret room was. "In here", Luke said pressing his hand on a section of the wall, making it slide back. They entered the room and were immediately grabbed by a Slitheen in a human disguise. Luke by a black man; Sarah Jane by Janine and Jenna by a plump man with glasses.

"Behold, the capacitor", Jeffrey said "We drain the energy into these and store it. In ten minutes this planet's atmosphere gets snatched away, but we'll be safe and warm in here".

"And then a spacecraft picks us up and we sell everything we've collected", Janine added.

"Why are you doing this?" Sarah Jane asked as the black man moved over to the controls, taking Luke with him.

"The Family came here once before, just a routine job, but they never came back!" Janine answered.

"That was my friend", Jenna said "he doesn't take kindly to those who try to destroy the Earth and neither do I!"

"They were our Family!" Jeffrey cried "This planet is going to pay in blood".

"Luke and Jenna are my family!" Sarah Jane exclaimed.

"This will give us a new beginning", Jeffrey continued "my son won't have to live like I've had to, cringing in the darkness". He put his arm around his son.

"I want my son and daughter to live, to grow up. I want what's best for them", Sarah Jane countered.

"Your stupid son gave us what we needed", Jeffery spat.

"I didn't!" Luke shouted.

"What?" Jeffrey asked.

"I thought I did, but I didn't. You made the mistake. When you showed me the diagram, you didn't tell me that you was going to steal power from the sun", Luke quickly explained "It'll explode!"

"It's a bluff", Janine scoffed.

"What's a bluff?" Luke asked confused.

"Florm?" Jeffrey asked Janine.

The woman shrugged "Well…the boy might be right", she said sounding unsure.

Parts of the machinery exploded with a bang. "It's happening! Turn it off!" Jenna ordered.

"You heard her, turn it off", Clyde said bursting in the room with Maria "There's vinegar in this!" he held up the orange plastic spray bottle. Janine shoved Sarah Jane over to Jeffrey and grabbed Clyde, knocking the spray bottle out of his hand.

"Water. That's a bluff", she said.

"I knew that wouldn't work", Maria told Clyde as she too was grabbed by a blonde woman.

"If I reset the system, you can cancel the overload, make it safe?" Jeffery asked Luke.

Luke nodded "Yes", he confirmed. He locked eyes with Jenna, trying to convey a silent message. Jenna gave him a small smile to tell him she understood what he was trying to convey.

"Right. Son, reset the system", Jeffrey told Carl. The young Slitheen pushed a big lever upwards. Outside the sun turns back to normal.

"It's reset. The systems off", Luke said as Jenna slowly reached into her pocket, pulling out her sonic "Now I just have to synchronise the mega-wattage….Now!"

Jenna, Sarah Jane, Maria and Clyde suddenly freed themselves from their captors. "Luke heads up!" Jenna called before she threw her sonic to him. Luke caught it easily and ran. A couple of Slitheen chased after him, Jenna hot on their heels.

"Leave him alone!" she shouted snatching up a piece of pipe, whacking Jeffrey hard on the back. This move got Jeffrey to have his attention on her which gave Luke the chance to use the sonic on the machinery, cutting the wires. The machines started going critical.

Due to this most of the Slitheen beamed themselves away. Luke, Jenna, Sarah Jane, Maria and Clyde sprinted out of the room. Jeffrey and Carl hurried after them but the door slid shut, trapping them.

"You can't leave us in here!" Jeffrey cried "Use your sonic device, open the door. Open the door!"

"I'm only 12!" Carl added. Despite him being a Slitheen and the fact that he'd tried to kill her brother earlier that day, Jenna's heart went out for him. He was just a kid.

"He's my son. Please, let him live", Jeffery pleaded.

"Luke", Jenna said holding out her hand for the sonic. Luke gave it to her but before she could act, Jeffery was disintegrated and then Carl exploded. The door closes and the lights come back on.

"It burnt itself out", Luke said.

"We did it!" Clyde added happily.

"He was a child, 12 years old", Sarah Jane said quietly.

"It was them or us", Clyde told her. Jenna said nothing, she just stared at the door, the sonic loose in her hand. If only she'd been quicker… she might've at the very least saved the young Slitheen.