The episode opens with the Lyoko Warriors in the lab, watching Jeremie analyze recently retrieved data from Sector Five, hoping it will be useful in finding a way to fight X.A.N.A. on the internet. They return to campus, where Jeremie, Aelita, Ulrich, and Odd have gym class. Instead of receiving a lesson on shot put as Jim had planned, they celebrate "Nutrition Day" by discussing dietary health with Yolanda Perraudin, the school nurse. It is implied the discussion is part of a new healthy eating campaign at Kadic Academy, much to Odd's annoyance.
At lunch, Jeremie and Aelita decide to skip their afternoon classes and return to the Factory to further analyze the recent batch of data. Once there, they discover an activated tower in the Mountain Sector and inform the others. Yumi leaves her Italian class with William under the pretense of taking him to the nurse, but she manages to slip away from him in the courtyard and arrives at the Factory. Meanwhile, Odd, who is unsatisfied with the new, healthier lunch menu, attempts to sneak into the school kitchen with Ulrich to find something better to eat.
It is then revealed that X.A.N.A. has possessed the foods in the kitchen. Food products begin flying into the courtyard, smashing windows and conglomerating into a large monster that attacks Ulrich, Odd, and Jim. Ulrich calls to inform Jeremie of the attack, and Jeremie decides to send Aelita and Yumi to Lyoko without the boys.
Yumi maneuvers the Overwing through the Mountain Sector while Aelita snipes several Krabs that are following them. However, as they approach the activated tower, X.A.N.A. manipulates the Digital Sea, causing its level to rise and slowly engulf the whole sector, efficiently blocking access to the tower. Jeremie also discovers that the Core of Lyoko in under attack in Sector Five and realizes that X.A.N.A. wants to stop Yumi and Aelita from deactivating the tower and from protecting the Core of Lyoko by raising the Digitial Sea. Meanwhile, Ulrich, Odd, and Jim are chased through the woods by the food monster, and Jim is knocked unconscious.
Unable to deactivate the tower, Yumi and Aelita decide to go to Sector Five, where Aelita may be able to find a way to lower the Digital Sea level. However, before they reach the edge of the sector for Jeremie to send the Transport Orb, they are attacked by a swarm of Hornets. Meanwhile, on Earth, Ulrich and Odd manage to get to the sewer access in the woods, and Ulrich lures the food monster in the wrong direction while Odd rushes to the Factory. In her battle with the Hornets, Yumi is knocked off the Overwing, and Aelita is forced to devirtualize her to prevent her from falling into the Digital Sea.
Ulrich's cell phone is damaged when he jumps into sewage water to avoid the food monster and is rendered unusable. When Jeremie is unable to reach Ulrich, Yumi leaves the lab to search for him. Meanwhile, Odd arrives at the Factory and is virtualized onto Lyoko. He arrives at Aelita's position and escorts her to Sector Five. Ulrich manages to get to the Factory, and Yumi meets him on the main floor.
Yumi is attacked by the food monster, and Ulrich saves her by temporarily incapacitating it before going into hiding. In Sector Five, Odd and Aelita travel to the Celestial Dome, where Aelita begins working at the interface to try to lower the Digital Sea level. Odd reenters Sector Five through the southern access point and begins battling several Mantas to defend the Core.
Aelita finds the data she is looking for, but is attacked by a Creeper. Odd defeats all of the Mantas, keeping the Core safe, while back on Earth, Ulrich and Yumi are cornered by the monster. Aelita defeats the Creeper and successfully uploads the data to Jeremie, who uses it to lower the Digital Sea.
Aelita and Odd return to the Mountain Sector and drive to the activated tower on the Overbike. When they are confronted by two Tarantulas, Odd and Aelita bail from the vehicle, allowing it to crash into the monsters, defeating them. Aelita then deactivates the tower, saving Ulrich and Yumi from the monster, which collapses into a massive pile of food products onto the Factory floor. Odd advises Jeremie to launch a return to the past so that Jim will forget his encounter with the food monster. As the return trip is being activated, Odd shouts out "I'm so hungry!!!" and the episode closes.
- The original French name for this episode is Raz de marée, which translates to Tsunami in English.
- This is the first episode where the title card shows the Holomap of Lyoko instead of a tower.
- This episode marks the second and last time where the entrance to the core zone in Sector Five twists open; the first time was in A Fine Mess.
- This episode marks the only time where a Creeper "hatches" from the wall of the Celestial Dome.
- The tower activated in this episode is the same tower X.A.N.A. activated in A Great Day.
|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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