I don't own Harry Potter or Code Lyoko.

Holiday in the fog

"You're going to do WHAT?!"

"I'm going to graffiti the wall so I can get detention," repeated Jeremy.

"Are you mad? You know that I'm going to be here as dad gave me permission and I can keep an eye on Lyoko and help with any towers that activate. And, if you did get detention, you'd have to clean it up, reducing the amount of time you can work on Lyoko."

"I know."

Harry sighed. "If you're going to do this, use easy paint to wash off. That would give you an easier time since it won't take as long to wash off. Oh, this conversation never happened."

"How did you get permission to stay here over the holidays anyway?" asked Jeremy.

"Oh, there's a programming competition on next week. I entered and dad let me stay here and program since I'm less likely to be distracted here. Though if Xana does attack, I would go help."

Outside

Jeremy and Ulrich ran to one of the buildings and started to paint.

Jim's room

Odd released Kiwi into the room. Kiwi then proceeded to bark, pulled the cover off the bed, peed on it, licked Jim's face and breathed on him. This caused him to wake up and start to chase him.

"Way to go Kiwi," said Odd.

Outside

"Come here, you mangy dog!" yelled Jim.

"That's my cue," said Ulrich as he ran off.

"This is for peeing on my bed," yelled Jim as he ran past the graffiti wall. "What's this meant to be? Jeremy? Did you do this?"

"If I had more time, I would have done better on the eyes," said Jeremy as Jim stared at the picture of him. "The paint wasn't good quality either."

Principal's office

"I hope this has taught you a lesson," said Delmas. "I don't understand though. Why would a model student life you decide to do something like this? You should be ashamed. Did you do it to be with your friend?"

"Yes sir."

"What did you get?" asked Harry.

"The whole holiday in detention," replied Jeremy.

"As you planned."

"Now, if Xana does attack, I can get a hold of every one."

"Why does Jeremy seem happy to be punished?" asked Nicholas.

"And who's this Xana?" wondered Sissi. "Ones thing for sure, they're hiding something."

"Daddy, I need to talk to you," said Sissi as she barged into the office.

"Sissi, I'm busy. I do have to manage the school, you know."

"It's not going to take long. You see, there's this girl I know that is falling behind on her schoolwork. However, she's going to see her grandma and once she gets there, she won't feel like doing her work. She really needs your advice."

"Well, if I were her, I would give up her holiday to study. Who is this girl?"

"It's me! Thank you so much. I promise to study hard!" Sissi ran out in joy.

School entrance

"Man, it's going to be strange being here without anyone," said Harry.

"Well, Odd's off to the other end of the planet, Yumi's going to the mountains and I have to have a maths tutor," said Ulrich. "At least you don't have to sit through that."

"It's a good thing that programming can't really be taught by a conventional tutor. Also, I'm probably better than any tutor our parents can get."

"Are your parents trying to correct your habits?" asked Odd. "If so, good luck to them. That's like mission impossible."

"Are you two sure that you're going to be alright on your own?" asked Yumi worriedly.

"We're sure," said Harry. "What's the worst that could happen?"

"Anyway, it gives us time to work on Aelita's materialisation program," said Jeremy.

"Oh, don't worry. They're not going to be on their own," butted in Sissi. "I'm staying at school too. I'll look after them."

"That was the worst that could happen. Except for… a certain something deciding to rear its ugly head."

"Alright young man," said Jim as he walked up. "It's time for you to start clearing up your mess. NOW!"

Sissi started to laugh.

"Laugh while you still can Sissi. You have to do your work as well and I have to keep an eye on you." He turned to Harry. "You don't have to be under my eye though. In fact, Mr Delmas didn't give me any instructions regarding you."

"That's alright. I can always bring my laptop outside if you wanted me to though you'd have to find an extension cable or something. That way, you can keep an eye on all three of us."

Jim scratched his head in thought.

Graffiti Wall

"Come on, you can put in more elbow grease than that," said Jim, despite the fact that Jeremy was more than halfway through.

"And how are you doing on those math questions," he asked Sissi. "Making any progress?"

"No but I was thinking I could give Jeremy a little help."

"Good idea. I'll go get you the items now."

With that, Jim walked off.

"Did your friend Xana help you with that?" asked Sissi.

"Xana's not my friend," said Jeremy.

"Oh, is she one of your friend's girlfriend then?"

"No. It's the name of a programming language Harry likes to use. I doubt you've heard of it," said Jeremy as he rubbed harder. "Can you go now?"

"Do you think I'm an idiot?"

"You said it, not me. Now, I want to get this cleaned up." With that, he turned back to the wall.

"Here you go." Jim shoved a sponge and a brush into Sissi's hands.

Sissi's dorm

"Oh, I've never been this sore," moaned Sissi over the phone to Herb.

"Sissi, you should go to sleep. It's late," said Herb.

"I can't. Jeremy and Harry might try something tonight, like seeing this Xana friend of theirs. They're up to something." Sissi used her mirror to spy on the door to Harry's and Jeremy's dorm. "I'm going to play super spy."

Harry's and Jeremy's Dorm

"I need to go to the lab to check something," said Jeremy.

"Do it tomorrow, Jeremy. It's late so you should get some sleep," yawned Harry.

"It doesn't matter if I remain on Lyoko for one more day," agreed Aelita.

"It's fine for you but if Sissi keeps poking her nose into this, she'll eventually find out about Lyoko and you. Then she'll spoil everything, like when we first turned on the supercomputer," said Jeremy.

"Thank you. Thank you, the both of you, for what you are doing."

"Ah, it's nothing," said Harry. "Although, the threat of Xana is nothing to laugh at but it's also given us a chance to make new friends."

Jeremy then slipped out of the dorm, snick past a sleeping Sissi and out of the dorm building to the boiler room. However when he went past a storage room, he heard a noise.

He opened the door and saw lots of gas. It was so thick, it started to make him cough so he quickly shut the door. Suddenly, he was grabbed from behind.

"Now, don't give me any of the usual reasons for being out of bed, I've heard them all," said Jim. "I've been working here for over twenty years."

"There's a lot of smoke in that room," Jeremy said, pointing at the door. Opening it, Jim stared at the wreckage.

"More like a hurricane. This better not be you're doing, Belpois," said Jim as he shooed Jeremy out of the room and shut the door

"Where did the smoke go? Not even a trace."

Harry's and Jeremy's dorm

"You better not leave this room again," said Jim. "Tomorrow, I'm calling your parents. You've got some explaining to do."

"I see you got caught," commented Harry. "What happened?"

"Aelita we have a problem," said Jeremy.

"Xana's woken up, but I don't know where the tower is," reported Aelita.

"A Xana attack?"

"Yes. Smoke."

"Smoke?"

"Yes. In one of the storerooms, there was a lot of smoke but when Jim checked, it had gone."

"Xana? And smoke?"

The next morning

The smoke had gone into the vents because, by the morning, it had covered the grounds.

Sissi was sleeping, unaware of the danger outside and inside as the smoke reached the vent over her dorm and went into it.

"Time to face the music," said Jim as he reached the right door and opened it to find it empty. "Huh? JEREMY!"

This caused Sissi to wake up. "What's happening? What's going on?"

She screamed when she saw the smoke and Jim came running.

"Jim! Smoke!"

"What's happening? Is this thing contagious or something?" asked Jim before seeing the smoke.

Factory

Jeremy and Harry stood in the lab.

"This is worse than I thought," stated Jeremy. "The gas can be deadly if you inhale it for extended periods of time because of the toxic materials. Aelita, the tower's in the forest sector."

"So, who's deactivating the tower?" asked Harry.

"We'll try to get both of you over to the tower," said Jeremy. "That way, if you get devirtualised, Aelita can deactivate the tower."

"I need help," said Aelita. "I'm quite far away from the tower."

I need to call the others."

"Use my phone," said Harry as he handed it to Jeremy.

Ulrich

Ulrich was in the middle of a lecture about how to do maths when he heard his mobile go off.

'S.O.S Xana.' He read.

The tutor didn't even notice him slipping out of the room as she kept on talking.

Odd

"Hey, what's this?" asked the customs officer at the airport.

"It looks like a skeleton," said another. "What is it kid?"

"It's a skeleton of a dog."

"It's moving."

"Oh, that would be Kiwi, my dog. He's not supposed to be there."

"Dogs are only allowed in the luggage compartment."

"He was supposed to stay here with my grandma."

Odd's phone went off.

"Oh, hey Grams."

"Grams? It's Jeremy, not your grandma."

"I know it's you. I know you don't like me calling you that. Ok, see you. I'll bring Kiwi."

Yumi

"We should have left hours ago," complained Mr Ishiyama.

"You know how much she likes her clothes," said Yumi.

"I don't even know what she's talking about."

"I'll be down in a couple of seconds!"

Yumi's phone rang.

"You're going to laugh when I tell you…"

"I really don't feel like laughing," said Mr Ishiyama as he cut his wife off. "Haven't you noticed someone's missing?"

Factory

"Alright, that's everyone," said Jeremy. "Now I'll virtualise you to help Aelita. I'm sending you to the desert where she is. Go to the scanners."

"Alright," said Harry as he headed to the lift.

"Transfer Harry. Scanner. Virtualisation."

Lyoko

"Hello Harry."

"Hi, Aelita. How's it going?"

"Oh, as always. Shall we go to the tower?"

"Might as well if we want to stop Xana. Which way is it?"

They started running in the right direction with Aelita leading the way. Once they got there, they entered it and jumped off the platform to the forest sector.

"Ok, we're in the forest sector," said Harry to Jeremy.

"Right. Be careful, you two. Xana's going to be sending some monsters after you. I'm going back to school to check up on Sissi and Jim."

Kadic

Sissi and Jim were hiding in a corner as the smoke crept up the corridor. Sissi was shaking.

"Oh, no" she whimpered as the smoke surrounded them and they started coughing.

"Over here!" Jim led them to a cupboard with no ventilation.

"Help," they yelled, with no one responding.

"It's no use," said Sissi as she slipped down the wall. "There's no help."

"Don't give up hope. I'm sure Jeremy's around."

Outside

"Sissi? Jim?" Jeremy called then he gasped at the amount of smoke covering the ground. It started to surround him and he started to cough when Yumi and Ulrich appeared and got him out of it.

"Jeremy!"

"Jim and Sissi are still inside," Jeremy said weakly. "We've gotta find them. Harry's on Lyoko with Aelita."

"I'll go look for Jim," said Ulrich.

"Wait!"

"Yumi, we have to go to the factory to help Aelita and Harry."

Yumi helped him to stand.

"Hang on Jeremy." She said as she helped Jeremy to walk when they met up with Odd.

"Where's Ulrich?"

"He's gone to help Sissi and Jim."

With Sissi

"I only stayed at school so I could find out what secret Jeremy and friends were hiding," said Sissi. "But is seems so hopeless."

"There's no ventilation in this room," said Jim. "We're going to run out of oxygen sooner or later."

"I'd better stop talking then."

Factory

The news was reporting the smoke and advising people to stay inside.

"Odd, help me over to the computer." Odd and Yumi looked at him. "And get ready to dive in. Stop looking at me. We haven't got time to lose."

Once they helped Jeremy over to the seat, Odd and Yumi went to the scanners.

"Transfer Odd. Transfer Yumi. Scanner Odd. Scanner Yumi. Virtualisation."

Lyoko

"Now where?" asked Odd as he and Yumi looked around. "Did something just touch me?"

Harry bust out laughing.

"Ha ha, very funny."

"The activated tower is this way," said Aelita as she stepped out from behind a tree.

"Seen any monsters?"

"Not yet," said Harry. "But that doesn't mean that they're not here."

"You can't have looked too hard," said Odd as he pointed at the Kankrelats that were advancing towards them.

"Whoever destroys the most of those critters wins"

"My type of game!"

With Ulrich

"How's it going?" asked Jeremy.

"I haven't found them and I've searched most of the building," reported Ulrich.

"You should get out of there soon. The smoke is poisonous!"

"I'll just check one more room," Ulrich coughed out as he tried to open another door.

"Jim? Sissi? Are you in there?" he asked just before he dropped unconscious and pulled inside.

"Ulrich? Ulrich? Harry's going to kill me!" moaned Jeremy.

"See, I told you that Jeremy was going to come for us," grinned Jim."What the... Ulrich?!"

"He came to save me," cried Sissi.

"Look, a phone. We can call for help."

"Jim?"

"Oh, Jeremy. Can you come and get us? We're running out of air and Ulrich's unconscious."

"I see what I can do."

Lyoko

"You need to hurry. Jim, Sissi and Ulrich are going to die if you don't."

"Well, it's not exactly a picnic over here," said Harry as he got two Kankrelats.

"Yeah, what do you think we're doing? Getting a suntan?" asked Odd as he got another.

Yumi hit the last one with her fan.

"Come on Aelita, let's go before more monsters turn up," called Harry.

"You spoke too soon Harry," Yumi said as three more Kankrelats turned up as they started running. "Though I do see what the others mean about you dodging," she added as Harry dodged a shot.

They came to a split. Harry and Aelita took one split and Odd and Yumi took the other. Two of the monsters followed Yumi while the other followed Harry, which he took out easily enough. When they got to the point that the paths meet up, they saw Yumi get devirtualised.

"Oh, great. Now I probably have Yumi's powers too," groaned Harry.

"You do."

"I really hate that power. Why do I even have it anyway?"

"Do you want me to get rid of it for you?"

"No. It's a moral thing. I just don't like the fact that I take the others powers."

"I really don't see why you're complaining," said Odd. "It just means that you're the most powerful of us. Ow!"

They turned to see a Krabe.

"You get Aelita to the tower Harry. I'll deal with old seafood here."

Harry nodded as he pulled Aelita onto his back.

"Hold on tight," he advised as he ran at top speed.

"Now, to deal with you," said Odd as he leaped and shot at the weak point. Unfortunately for him, the Krabe hit him as well which caused him to devirtualise.

With Harry

"Here we Aelita," Harry said as he slowed down. "I hope you're not too dizzy."

"How can you see at such high speeds?" asked Aelita. "All I saw was a blur. I don't think I can even move at the moment. And why don't you just go to the tower yourself?"

"Everything slows down for me when I move that for why I don't go straight to the tower, it's like Jeremy said earlier. If I get devirtualised, you'll have to come to the tower and deactivate it and the time would have been wasted. Anyway, if you're with me, I can help stop any monsters."

"Not that I want to stop this conversation," interrupted Jeremy. "But we're on a time limit here!"

"Ok, I'll get the tower. I don't think Aelita is able to walk."

Harry jumped over to the tower after making sure Aelita was safe and entered it. He walked over to the centre of the platform and rose to the next level. He put his hand on the screen.

Harry

Code

Lyoko

As always, the files flew down the inside of the tower before a white light came flying up.

Lab

"Return to the past, now," said Jeremy as he launched said program.

A white dome expanded from the factory and engulfed every thing.

The previous night

"You do know that Xana isn't going to attack for a while," said Ulrich.

"I don't think he'll be too unhappy with this," replied Jeremy, looking at the picture of Jim who had a crown on.

"You know, I might stick around. It gets me out of math tutoring," Ulrich said as Jim ran after Kiwi.

"Do you think that Sissi will stay behind again?" asked Harry.

"Probably," said Ulrich. "She can't stop following me. Can you show us what you can do with your power?"

Harry started concentrating and a pen started to rise, stopped and a copy appeared next to it.

"That is so cool," said Odd. "Can you copy your homework for me?"

"I've already told you no, Odd!"

"You're a real spoilsport, you know that?"

"You just made yourself a bigger target," said Yumi. "Xana will do anything to get rid of you."

"Don't remind me."