When Susan gives a lesson on nanotechnology, she has small machine designed to produce the little robots as an example. Little do they realize that X. A. N. A. has infected the machine, so when they find it filled with gel, Odd carelessly ends up pushing Ulrich's face into a small scoop of it. Later on, Ulrich gets a headache and faints. When he wakes up, his memory is gone. Sissi is there at the time, so she uses Ulrich's memory loss to convince him that she's his girlfriend. As the rest of the group tries to bring him to his senses, more cases of amnesia occurs, spreading from person to person like a disease. Only after most of the school is affected, Jeremie realize that X. A. N. A.'s produced nanotechnology is responsible. Ulrich goes for backup with amnesia until the tower is deactivated.