Jeremie is up late at his computer running five dry runs on Aelita’s materialization program, with success in all. After informing Yumi, she tells her parents next morning about Aelita staying with her, under the guise of “Aelita Lyoko”, her Japanese pen pal. Her parents approve. Around the same time, Odd and Ulrich are speaking with Principal Delmas about enrolling Aelita at Kadic Academy. To do this, Odd forged a recommendation letter in his parents name, with a successful result. Jim catches them on the way out, stating that one day, he will find out what they’re hiding.
Jeremie announces to his friends that he has completed his materialization program for Aelita. They want to try it out after class, but Jim catches them in the act, saying that they're going to stay put until they tell him what their secret is. Jim even calls the team "these little devils", indicating his overly strict paranoid attitude. However Principal Delmas shows up just in time and scolds Jim for being paranoid and tells him to leave Jeremie, Odd, Ulrich and Yumi alone as he is a gym teacher not a detective. This only angers Jim who lashes at the Lyoko Warrios and tells them to go to their classes.
On Lyoko, Aelita enters the Forest Sector and runs towards the way tower but she finds it guarded by some monsters. Jeremie gets the message on his laptop and after the class, they head to the Factory, where Jeremie virtualizes Odd, Yumi, and Ulrich to the Forest Sector. They destroy the monsters without much trouble and enter the way tower. When Jeremie places the CD into the supercomputer, he is shocked that it is the wrong one; all it contains is a music video for Odd's song. Jeremie must go back to his dorm room to pick up the right CD, while the others wait in the tower until he comes back.
Jeremie manages to get to his dorm room and retrieve the real CD. However, Jim once again finds him. Still determined to discover their secret, Jim chases him down the steps and orders him to stop. Jeremie tumbles on the stairs and breaks his ankle during the heated chase, causing some of the students who watched him fall to blame Jim for the accident, including Heidi Klinger. Jeremie is taken to the infirmary, and Jim is fired by Principal Delmas for allowing his paranoid actions to cause an injury to a student.
Jim begins to feel guilty for what he has done and decides to go into the infirmary to apologize to Jeremie. Jeremie, who is now stuck in the infirmary with no way to reach the others, who are still on Lyoko, decides to tell Jim the truth; his suspicions were right all along. He offers to tell Principal Delmas the whole thing, about Lyoko and the Factory, so that Jim can get his job back, on the condition that Jim carries him back to the Factory. Jim agrees and takes Jeremie there.
While the others are patiently waiting in the tower, a Megatank shows up and starts attacking the tower making everything inside shake. Ulrich, Yumi, and Odd leave the tower to protect it, but the Megatank devirtualizes Yumi and Odd. Ulrich manages to destroy it, but another one shows up to destroy the tower before Aelita can be materialized to Earth. Ulrich tries to protect the tower from the second Megatank's laser with his katana as long as he can. In the meantime, Jeremie loads the Materialization Program.
Aelita stands in the middle of the platform, rises up until the middle of the tower where the program starts to work. Ulrich, still protecting the tower, is soon devirtualized by the shot of the Megatank and the shot also hits the tower. The tower still holds thereafter, and inside it, Aelita starts to devirtualize for the first time. X.A.N.A. tries to stop her, but he is too late; Aelita appears in one of the scanners. She opens her eyes and sees Jeremie and the others. Jeremie happily welcomes her by saying, "Welcome to Earth."
- The original French name for this episode is Code Terre.
- In terms of production order, despite being the head writer for the first three seasons of the series at the time, this was the first episode in which Sophie Decroisette was credited as writer on the title card.
- Jim is made a team member in this episode, albeit temporarily.
- In this episode, it is revealed that Odd made a music video called "Break, Break, Break Dance!". Several minor characters appear as background dancers. Jeremie called it "dumb", after mistaking the CD with the video for the CD with Aelita's Materialization Program. The lyrics are "Break, Break, Break Dance!", "Break, Break, Break Dance!", "Break, Break, Break Dance!", "Here we go!".
- Aelita arrives on Earth for the first time in this episode.
- From this episode onward, the Megatank's laser can devirtualize Odd, Ulrich and Yumi instantly with a single hit.
- This episode was released in book form, but only in French.
- When the group arrives at the tower, it has a red halo, as if it is activated. A couple of scenes later, it's deactivated, and then activated again.
- When Jeremie asks Yolanda if he could use the bathroom, she says the doctor insists that Jeremie stay off his feet, even though it was actually Yolanda herself who told him this.
- When the elevator's doors are opening, one of Jeremie's legs was lifted, but when the gang (with Jim) is in the scanner room, who are waiting to see Aelita, Jeremie put both of his legs on the ground. It is also worth noting that the nurse also told him that he can't put his feet on the ground for a whole week.
|Code Lyoko: Season 1|
|X.A.N.A. Awakens | Teddygozilla | Seeing Is Believing | Holiday in the Fog | Log Book | Big Bug | Cruel Dilemma | Image Problem | End of Take | Satellite | The Girl of the Dreams | Plagued | Swarming Attack | Just in Time | The Trap | Laughing Fit | Claustrophobia | Amnesia | Killer Music | Frontier | The Robots | Zero Gravity Zone | Routine | Rock Bottom? | Ghost Channel | Code: Earth | False Start|
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