Jérémie, Aelita, Yumi, Ulrich, Odd and William return to their daily lives as students of Kadic College. But XANA, the multi-agent program that had become their mortal enemy and that they had managed to destroy in their previous adventures, reappears. The Lyoko Warriors reactivate the supercomputer in order to return to Lyoko, discover the reasons for this reappearance and put an end to it before the Earth is threatened again.

Candice Renoir had put her career on standby for 10 years. When she returns from Singapore to resume service in a port town in the south of France, she feels a bit “rusty”. Despite the obvious defiance of her unit and a cynical superior who doesn’t make her job any easier, she is determined to turn her so-called weaknesses into strengths, solving the most complex cases with her common sense, her acute observation and her practical nature seasoned by a busy daily routine. Only Candice can catch a killer because she knows the chemical composition of a window-cleaning product or determine the hour of a murder from the cooking-time of kebabs… Candice is only naive on the outside, and nobody can resist her!