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 Jean-Pierre is missing.
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 principle 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 evidence points to Jeremie as the culprit. However the agents also believe Jeremie must have access to a supercomputer of his own, and begin surveiling 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 increase their surveillance, employing Jim to plant a tracer on Jeremie so they may 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 what X.A.N.A.'s plan is, Jeremie begins the manual devirtualization process, but is stopped when 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.
Aelita, Odd, Yumi, and Ulrich become suspicious when they notice Jeremie is gone, and Ulrich volunteers to return to Earth and investigate. Devirtualized, 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 hides.
Meanwhile, back on campus, Jeremie is interrogated by the other agent. 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. Jeremie's laptop then begins to beep, and it is revealed that X.A.N.A. has activated a tower in the Mountain Sector. As the agent inspects the laptop, a spectre emerges from wiring in the ceiling and possesses him. The possessed agent begins attacking Jeremie, and Mr. Delmas 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 destroys the Scanners. Now able to access the interface, Ulrich makes contact with Aelita, Yumi, and Odd, and informs them of the new activated tower. With Aelita's guidance, Ulrich is able to tell her the location 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. 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 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 manages to deactivate it, saving Jeremie and Ulrich. Jeremie then performs a Time Reversion to fix the Scanners and erase Jim's 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 the other Lyoko Warriors stole it from him and 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.
- Aelita does not appear to know how to fly using the Overbike.
- In the scene where Ulrich is looking at the Supercomputer Room security camera, the white agent is damaging the Supercomputer. This is a mistake; the white agent was on campus with Jeremie, while the black agent was the one in the Factory.
- After Yumi defeats the Megatank, Odd is shown on his Overboard. However, the board had already been destroyed by that point in the battle.
|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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