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In a prequel to the series, Jeremie discovers a supercomputer in an abandoned factory. Within, he finds an artificial intelligence he decides to name Maya. With the supercomputer active, strange events begin to plague Jeremie. Meanwhile, the rest of the group begins to meet one another. Ulrich and Yumi end up in the same martial arts class and Ulrich gets mad when he gets beaten by Yumi. Odd is new in school and brings along his dog Kiwi. Odd gets roomed with Ulrich and Kiwi tears up Ulrich's things. Ulrich and Odd go into the virtual world for the first time.

Realizing the danger the supercomputer represents, Jeremie takes the advice of his new friends and decides to shut it down, but not before bringing Maya into the real world. Meanwhile, the strange events become a consistent problem when an electric orb begins hunting Jeremie and his friends. In a trip to Lyoko, Ulrich, Odd and Yumi work together to get Maya to the tower under the assumtion that it will bring her to the real world. This assumption is ultimately false, shutting down Xana's attack rather than materializing her. Maya (who discovers her real name of Aelita when shutting down the tower) suggests they shut down the supercomputer, but the group decides to help Jeremie until Aelita is in the real world.