Code Lyoko

X.A.N.A. launches an attack on the Internet itself, managing to disable much of the city's infrastructure. Though most of the problems caused can be bypassed by manual controls, two trains that are completely automatic are put on a collision course, one of which contains a load of highly and deadly toxic chemicals. Yumi and Ulrich go to help Aelita, but Odd is forced to stay because Sissi tells on him to Jim for having Kiwi since he pulled a prank on her.