A new girl-genius and highly gifted teenage girl named Laura Gauthier tries to join the quintet at Kadic Academy. She humiliates Jeremy by correcting his mistakes on a complex exercise in class. Aelita suddenly is resentful and suspicious of this new girl, who seems to want to discover their secret. Meanwhile, Jeremy informs his four friends that he has programmed a new vehicle that is made for travelling through the Cortex easily called the Megapod. Once on the Cortex, they are impressed by the new cruiser, which Yumi ends up driving. Unfortunately, Laura follows William to the factory and discovers the lab and Supercomputer, which she is very interested in. During a battle with several Krabes, Aelita, Odd and Ulrich are devirtualized, leaving Yumi trapped in the Megapod. With Laura's help, Jeremy fixes the bugged vehicle and Yumi is returned to Earth just before the Megapod falls into the Digital Sea.

Jeremy tries to create a virus to destroy the Cortex, however it doesn't work and the group discusses what to do. They decide to bring Laura to the factory and Odd steals her tablet and runs, with Laura chasing after him. When she gets there the gang explains about XANA and the Cortex and that they need her help, which she accepts to give. She easily fixes the problem and they launch the virus and a return to the past. Laura forgets everything, but thanks to a few hidden commands in the virus, the code for the return to the past was altered to exclude Laura, causing Laura to start having memory flashbacks of her time in the lab. She follows the memories to the sewers. William (who was left on Earth) tries to stall her, but fails, and Laura ends up back at the lab. Meanwhile, Ulrich and Yumi encounter Ninjas in the Cortex for the first time, but are unable to defeat the new monsters and are sent back to Earth in no time.

Jeremy is woken up by the Superscan when it picks up two activated towers. He warns the others, and just as they're leaving Aelita receives a message from an unknown sender asking her to meet them in a nearby building. While she's thinking about it, Laura comes and asks why she's not in class, then realizes that the others are at the factory. Aelita tells her to go on ahead, which she happily does. Aelita then goes to the meeting place and finds a blonde-haired woman there; her long-lost mother, Anthea. They share a warm mother-daughter embrace. Jeremy offers Laura the controls and goes to find Aelita, realizing her "mother" is actually a spectre, and tries to convince her of it. Aelita doesn't believe him and returns to the spectre. Meanwhile, Laura figures out XANA's strategy; activating the two towers one after the other in a specific sequence of prime numbers.

A computer error causes the science test scores at Kadic to be messed up, as well as bugging up the rest of the computer system with it. Jeremy is alerted to an activated tower and he, Aelita, Odd, Ulrich and Laura go to the lab to check it out. Laura's dad is called to the school as a result of the marks mix-up and he calls her back to the principal's office. He expresses his doubt in her abilities and his wish for her to go to another school. Laura insists on staying, deciding to show him the Supercomputer as proof of what she can do. Meanwhile, the others explore Lyoko looking for the activated tower that's nowhere to be found. Jeremy eventually picks it up in the Cortex and sends them there to take care of it. When Laura and her dad arrive, Aelita goes back to the lab to get them out of Jeremy's way so the mission can be completed. The tower is deactivated and a return to the past is launched.

We don't have an overview translated in English. Help us expand our database by adding one.

We don't have an overview translated in English. Help us expand our database by adding one.

We don't have an overview translated in English. Help us expand our database by adding one.

We don't have an overview translated in English. Help us expand our database by adding one.

Jeremy manages to develop a program that will allow the gang to hack Tyron's surveillance system and spy on him, both using video and sound, and potentially speak to Anthea. When the gang go to the Cortex to implement it, all but Aelita are devirtualized by Ninjas when they tip off an unforeseen security system. Aelita opts to stay in the Cortex's core to wait for her mother to appear, asking for a clone to replace her at the school while she's gone, which causes enough problems of its own. In the end, Aelita is able to speak to her mother, convincing her that she is alive before she, too, is devirtualized by Ninjas. The experience initially leaves her feeling very sad, but after Jeremy assures her that Anthea got the message, her spirits are rekindled.

While the Lyoko Warriors prepare to take advantage of a sunny afternoon, XANA launches an attack, sending them a polymorphic specter disguised as...them, constantly changing its appearance! Plus, not content with fighting unexpected specters at the school, our heroes are confronted with false avatars of themselves on Lyoko. Paranoia will soon settle in. And it's chaos on Lyoko as more false avatars keep showing up one after the other.

We don't have an overview translated in English. Help us expand our database by adding one.

We don't have an overview translated in English. Help us expand our database by adding one.

We don't have an overview translated in English. Help us expand our database by adding one.