About the characters

- First episode in which Yumi uses her telekinesis to move a person.
- Odd is gifted in Italian, unlike Jeremy.
- In this episode, Aelita uses one of Yumi’s fans.
- Sissi is subscribed to a magazine called “Pretty Girl” and sleeps with a stuffed moose.

About errors

- In the English dub, Milly asks Sissi what she thinks about her father setting up a language exchange programme with France, which is silly because they live in France.
- The factory microphone changes often (wired or wireless).
- The cafeteria doors change colour often (grey, green).
- Christophe M’Bala’s headband is black during one shot in the cafeteria.
- Aelita’s outfit is reversed when she enters the tower!
- When Yumi leaves her house to go to the factory she’s carrying her bag, and when she arrives she doesn’t have it anymore.
- Herb’s glasses aren’t the same when he tells William that Jeremy and Aelita are trying to get out, and his hair is entirely black after Milly says that she wasn’t lying about Tamiya attacking her.
- The people under XANA’s control, including zombies, have great physical abilities. But why they didn’t simply break a window pane to attack the students in the cafeteria… We do however see Jim smash a chair with one hit, so breaking a window or a door shouldn’t be so difficult to do…
- In the very first shot of the cafeteria, we see that it’s daytime even though the kids are having dinner.

About the series

- French title: Contagion

- First time XANA makes an activated tower invisible, which it does again in episodes 47 “Tip-Top Shape” and 74 “I’d Rather Not Talk About It”.
- Only episode in which we see Aelita’s sixth sense (allowing her to see the invisible tower).
- New allusion to Dr Schrank from the series Hospital of Horrors.
- XANA’s spectre leaves the lamp on Odd’s desk just like in episode 31, “Mister Puck”.
- Yumi says a precognitive phrase about the vehicles: "Soon we’ll be landing right on top of them!"
16 episodes later, she and Aelita virtualise directly above the Overwing.
- This episode suggests that a majority of staff sleep at Kadic as well as Jim. Rouiller, Fumet and other teachers are present when this episode takes place at night.

About references

- Odd: “The better to pig out with, my dear!”
This references the French/European fairy tale Little Red Riding Hood, originally written by Charles Perrault. In most recent adaptations, when Little Red Riding Hood questions her “grandmother” (the wolf)’s strange eyes, ears, teeth, etc. the wolf replies “all the better to see/hear/eat/etc. you with.”

- Odd: "Oh great, William thinks he’s Bruce Willis, that’s all we needed!“
Bruce Willis, an American actor, has played three roles in films in which he’s humanity’s saviour.

- Odd: “Hey, Jackie Chan, so you think you’re the boss around here or somethin’?”
Jackie Chan (born Chan Kong-Sang) is a well-known actor, martial artist and stunt performer (among other things) from Hong Kong. He’s starred in many films and had his own animated TV series Jackie Chan Adventures.

- XANA’s technique is directly inspired by modern films about zombies in which the monsters infect healthy people through biting them.
The most prominent examples are the “Resident Evil” video games, adapted for cinema.