Odd and Ulrich are both woken up in the middle of the night by Odd's new virtual pet, Jean-Pierre. Meanwhile, as Jeremie sleeps, the desktop in his dorm turns on and begins performing tasks on its own. The next morning, Odd discovers that Jean-Pierre has disappeared.
While Odd laments the loss of Jean-Pierre at breakfast, two government agents arrive at the school and enter the office of Mr. Delmas, the principal of Kadic Academy. It is revealed by the agents that the supercomputer of a large weapons manufacturer was hacked the night before and that all the evidence points to Jeremie as the culprit. However, the agents also believe Jeremie must have access to a supercomputer of his own because he wouldn't be able to hack into another supercomputer by using the computer in his room, and begin surveilling him in the hopes of finding it.
As Jeremie and his friends search for Jean-Pierre, Mr. Delmas, the two agents, and Jim observe them via hidden recording equipment. When they overhear Jeremie mention Jean-Pierre, the agents assume he is referring to Mr. Delmas, whose first name also happens to be Jean-Pierre, and begin to suspect a kidnapping plot. The agents decide to increase their surveillance by ordering Jim to plant a tracer on Jeremie so they can monitor his movements more closely.
Just before lunch, Jeremie's laptop alerts him to an activated tower in the Ice Sector, and the Lyoko Warriors all make their way to the Factory through the manhole in the park. Aelita, Yumi, Ulrich, and Odd are then virtualized onto Lyoko. Meanwhile, Jim and the two agents follow them into the sewer and arrive at the Factory as well.
Odd, Yumi, Ulrich, and Aelita approach the tower, but soon discover it is not actually activated. Jeremie deduces that X.A.N.A. has found a way to fool the Superscan and wanted to lure them onto Lyoko. Unsure of what X.A.N.A.'s plan is, Jeremie begins the manual devirtualization process, but is stopped when Jim and the agents find their way into the lab and arrest him as a suspected terrorist. Unbeknownst to the others, who are still waiting to be devirtualized, Jeremie is taken back to campus for questioning by one of the agents while the other agent and Jim stay behind to figure out the origins of the supercomputer and the scanners.
The rest of the group becomes suspicious when they notice that Jeremie is gone, and Ulrich volunteers to return to Earth and investigate. After being devirtualized by Odd, Ulrich finds Jim in the scanner room, and uses his Pencak Silat training to knock him unconscious. He then climbs a ladder up to the lab, sees the government agent at the interface, and immediately hides.
Meanwhile, back on campus, Jeremie is interrogated by the other agent and Mr. Delmas. Ulrich calls Jeremie's cell phone, and when the agent answers, Jeremie shouts to Ulrich over the phone and instructs him to devirtualize the others as all of this is X.A.N.A.'s doing. The agent starts asking Jeremie who X.A.N.A. is and whether "she" is involved in the hack from the last night. Jeremie's laptop then begins to beep, and it is revealed that X.A.N.A. has activated a tower in the Mountain Sector - this time for real. As the agent inspects the laptop, a spectre emerges from wiring in the ceiling and possesses him. The possessed agent begins attacking Jeremie but Mr. Delmas tries to protect Jeremie from the agent and is knocked out in the subsequent struggle.
Meanwhile, the agent in the lab is possessed by a spectre as well and goes down to the scanner room, where he starts destroying the scanners. Now able to access the interface, Ulrich makes contact with Aelita, Yumi, and Odd, and informs them of the new activated tower but he doesn't know in which sector thus cannot guide them. With Aelita's guidance, Ulrich is able to tell her the coordinates of the new tower. However, it is revealed that the agent in the Factory is now trying to destroy the Supercomputer itself, causing strange glitches to occur on Lyoko such as dissappearance of various elements of virtual world and moreover with the turned off scanners they won't be able to return home if any of them are devirtualized. Ulrich leaves the lab to lure the agent away from the supercomputer while the others travel to the Mountain Sector. At Kadic, Jeremie manages to escape and runs into the woods, still pursued by the agent.
On Lyoko, Odd, Yumi, and Aelita successfuly change the sectors and manage to reach the activated tower despite the glitches and find it guarded by three Megatanks. Meanwhile, Jeremie and Ulrich meet up on the main floor of the Factory, and are soon cornered by both possessed agents. Yumi, Odd, and Aelita battle the Megatanks while Ulrich and Jeremie fight the agents. Aelita enters the tower and, despite the malfunctioning interface, manages to deactivate it, saving Jeremie and Ulrich. Jeremie then launches a return in time to fix the supercomputer, the scanners and erase Jim and the agents' memories.
After returning to the past, Odd sets up a video camera to find out what happened to Jean-Pierre, and it is revealed that the other Lyoko Warriors stole it from him, at Yumi's suggestion, because he was "starting to get hooked on him". The rest of the team then reveal that Yumi gave it to Hiroki. The episode ends as Hiroki accidentally kills Jean-Pierre and throws the toy into the street, where it is run over by a car.
- The original French name for this episode is Fausse Piste.
- Jean-Pierre is described as a Tamagutchi, a reference to a brand of real-world virtual pets called Tamagotchi.
- Jean-Pierre would later be mentioned by Odd and Ulrich in A Space Oddity.
- In this episode, Aelita does not appear to know how to fly using the Overbike.
- This is one out of the two times in the original series where a Megatank fires its circular laser horizontally.
- When Mr. Delmas, Jim, and the two agents are spying on the Lyoko Warriors and see Kiwi on the screen, Mr. Delmas asks Jim why a dog is present on the school grounds, and the latter responds with "I don't know, sir. It's the first time I've ever seen it." Yet in previous episodes such as Holiday in the Fog and Just in Time, it is clearly shown that Jim knows about Kiwi's existence.
- The activated tower was shown in two different places; the first time (in the moment in which X.A.N.A. activated it) it was on the platform between two mountains (later the Lyoko Warriors exited this tower when they moved from the Ice Sector to the Mountains), and the second time was on the large and empty platform.
- In the scene where Ulrich is looking at the supercomputer room security camera, the white agent is damaging the supercomputer. This is considered as an error because the white agent was on campus with Jeremie, while the black agent was the one in the Factory.
|Code Lyoko: Season 3|
|Straight to Heart | Lyoko Minus One | Tidal Wave | False Lead | Aelita | The Pretender | The Secret | Temporary Insanity | Sabotage | Nobody in Particular | Triple Trouble | Double Trouble | Final Round|
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