I do not own Code: LYOKO, but Eva and Kayla are both mine. This is the fourth installment of the Light and Shadow series. Other stories in the series include 1) Light and Shadow, 2) Memories of Light, and 3) Light on a Page. Feedback is welcome.

The LYOKO warriors were having quite a time against a group of monsters in the mountain sector. XANA had activated a tower and sent William to the core of LYOKO. Aelita, Kayla, and Ulrich went to deactivate the tower and Yumi and Odd had gone to Sector Five.

"Ugh! We could really use Eva right about now," Yumi said, tossing her fan to destroy a manta.

"Anyone know where she is?" asked Odd.

"I can't get a hold of her on her mobile," said Jeremy.

"You don't think that XANA got her, do you?" asked Aelita.

Ulrich snorted. "I would almost pity XANA if it tried. Almost."

Kayla bit her lip. This was the third time that there was a XANA attack and Eva was no where to be found. Was Kayla worried? Yes, and more than a little. This was not the Eva she knew. Eva would have been the first to jump into a fight if she thought she could protect Aelita.

They returned to Earth and found Jeremy trying to call Eva again. He shook his head.

"I've tried her number five times now," he said. "It's not going straight to voice mail so she has it turned on."

"Do you think something happened to her?" asked Odd. "Eva's tough, but she's still human."

"We'll find out tomorrow," said Yumi. "It's late. If my parents find me gone, I'll be grounded until I graduate."

"Same here," said Kayla.

That night, Aelita woke from a nightmare. She rubbed her eyes and heard a noise. She did not imagine it. It sounded like someone was walking down the hallway. Aelita got out of bed and poked her head out the door.

It was Eva! She was carrying a box and limping down the hall. She was dressed in her day clothes, a dark sweatshirt pulled over her oversized shirt with the hood up. She may not have been able to see her face, but Aelita knew Eva when she saw her. Her footsteps were light, but whatever she had in the box made a bit of noise.

What was going on?

During gym class, Eva dragged herself to the track. She was practically asleep on her feet.

"Hey," Odd whispered to her. "What's going on?"

"Yeah," Ulrich said. "XANA attacked last night. Where were you? Jeremy called you a bunch of times."

"Sorry," Eva muttered, keeping her head down. "I must have slept through it."

"Maverick!" shouted Jim. "Are you going to participate or not?"

Eva joined the team Jim placed her in for soccer.

"There is definitely something going on with her," said Ulrich.

Odd nodded in agreement. He looked over at Kayla, who seemed absolutely furious. Odd gave Ulrich a nudge and pointed. "I don't think we want to cross Kayla."

Aelita touched Kayla's arm. "Are you all right?" she asked her friend. "You seem upset."

"You have no idea," growled Kayla.

Aelita flinched and glanced at Odd, Ulrich, and Jeremy. This was not good.

At supper, Eva was not in the cafeteria.

"This is not good," said Ulrich.

"Did you see Kayla?" asked Odd. "I thought she was going to have the tantrum of tantrums. I would not like to be Eva."

"She hasn't been sleeping," said Aelita. "Last night, I caught her coming in after we came back from the factory. It must have been an hour or more after we deactivated the tower. She was carrying a box."

"What was in it?" asked Jeremy.

"I don't know," said Aelita. "Whatever was in it made a lot of noise. You know how silent she walks. I could hear her coming down the hall."

"I'm worried," said Ulrich. He looked over at the William clone. "I don't want her to go to LYOKO and XANA take advantage of her."

"I don't think I could take losing another friend," said Odd. "William was bad enough, but Eva. XANA would be invincible if it ever got its virtual hands on her."

"We have to find out what is going on with her," said Jeremy.

"How?" asked Odd. "She's so sneaky, it's like she has her invisibility here in the real world."

"We'll follow her," said Ulrich. "She's fast, but I can keep up with her."

"She's already left for the night," said Aelita. "What do we do until she comes back?"

They stayed silent for a long moment.

"It seems that we are missing someone." They turned to see Sissi and Herb standing beside their table. "Where's Eva?"

Jeremy turned to Odd. "Do you mind?"

"Aren't you missing something too, Sissi?" asked Odd. "Your brain, for example?"

Sissi walked off in a huff.

The remaining LYOKO warriors ate their supper quietly.

Eva came back to the dorms late that night. Standing by the main gate was someone dressed in black. Under the hood, Eva could see who it was.

"It's late," Eva said. "What are you doing, Kayla?"

Kayla walked up to Eva. "I could ask you the same thing," she said.

Eva walked passed Kayla and to the dorms.

"Eva, please," Kayla said, grabbing Eva's arm. Eva hissed in pain. "You're hurt!"

"Don't worry about it," said Eva, gingerly touching where Kayla had grabbed her.

"Eva, what is going on?" asked Kayla. "Where are you going?"

"At the moment, I'm going to my room to get some sleep," Eva curtly replied. "I suggest you do the same."

Kayla let out a heavy sigh before walking home. Eva was being stubborn and there was nothing Kayla could do about it.

Eva walked back to her room and heard a familiar, angry voice.

"Stop calling me!" Eva heard Sissi demand through the door.

Sissi stomped out of her room and headed for the showers, grumbling something about being beautiful and unwanted boys.

"Boy trouble?" Eva asked.

Sissi screamed and whirled around to face Eva. "What are you doing out of bed?" she demanded.

"I could ask the same thing," said Eva.

"I'm the principal's daughter," said Sissi. "I don't answer to you."

Eva nodded. "Very well," she said coolly. "Now, would you care to tell me about the heated conversation on your phone that most likely woke most of this floor?"

"Some boy keeps calling me," hissed Sissi. "I don't know how he got my number. He doesn't even go to this school."

"A bit of a problem you have then," said Eva. "Good luck with solving it."

"Um, Eva?" Sissi called after her.

Eva turned around.

"Do you think that you can help me?" Sissi asked. "I don't know what to do about it."

"My best advice is to ignore him and he will lose interest," said Eva.

"Thanks, Eva," said Sissi.

"You're welcome," said Eva. "Good night, Sissi."

Sissi stared at Eva as she went back to her room. "Good night, Eva," she muttered under her breath.

Eva went into her room and flopped onto her bed without first changing her clothes or pulling back the blankets.

While everyone was asleep, the super scan beeped. XANA had activated a tower.