S4·E26 Bad Connection

Odd is presenting one of his films, but is unhappy because his parents are coming. According to him, they never find fault in anything he does, which he finds dissatisfying because he isn't treated like a normal teen. However, when he's finally pressured into it, XANA attacks, using the school's cell phone antenna to spread a virus to everyone who answers their phone to cause them to become vicious, angry mind controlled slaves , starting with Odd's parents. With the widespread use of cell phones, all but the Lyoko warriors and Sissi are affected, Sissi having had her phone accidentally broken by her father. While she and Odd attempt to evade the possessed students and faculty, the others deactivate the tower in the Mountain Sector. Once a return trip wipes everyone's memories, Odd plays his video, which showcases all the humorous moments at Kadic, with Sissi in particular being treated in a positive light as thanks for her earlier assistance, much to her confusion.