|The Other Aelita|
|Air date||March 8, 2013|
|Written by|| Josep Maria Roca Peña|
A Travel Through Time,
The episode begins in Jeremy's room, Aelita and Jeremy are working on the computer to improve the Skidbladnir, and Odd makes one of his jokes. Jeremy goes to the Factory to continue their work while others go to class.
In gym class, Jim passes the list and see that Jeremy isn't present, but he isn't surprised, saying that it's normal to skip gym class. Meanwhile X.A.N.A. activates a tower and make a dark clone of Aelita with black hair, and when Jeremy will alert the other Lyoko-Warriors, the clone of Aelita throws Jeremy into the river and goes.
In Kadic, the real Aelita goes to the bathroom, where she finds the clone, who knocks Aelita. Then the false Aelita goes with the true Aelita and they go to Factory. The false Aelita virtualizes her double in the forest sector of Lyoko and X.A.N.A.-Aelita takes the real Aelita with X.A.N.A.-Sissi to throw her into the Digital Sea.
Meanwhile, Jeremy gets out of the river, but his mobile phone isn't working by water. He goes to the lab, and calls to the rest that they were eating. Odd and Ulrich go quickly to the factory and warn Yumi, who had gone home. She quickly leaves home and goes to the Factory too. On Lyoko, Aelita wakes up, but is on a Manta with X.A.N.A.-Aelita.
Aelita destroys the Manta with an energy field and jumps, but X.A.N.A.-Sissi recaptures Aelita. Jeremy virtualizes Odd, Ulrich and Yumi on Lyoko, and there appear flying Tarantulas. They start fighting them and also comes X.A.N.A.-Sissi. Odd then handles the flying Tarantulas, and Yumi handles X.A.N.A.-Sissi. Ulrich will prevent X.A.N.A.-Aelita to pull the real Aelita into the Digital Sea.
After a great struggle, X.A.N.A.-Sissi devirtualizes Yumi. Odd destroy all flying Tarantulas, but is devirtualized by X.A.N.A.-Sissi. Ulrich also manages to destroy Aelita's clone, but X.A.N.A.-Sissi appears and prepares to fight against Ulrich.
Then X.A.N.A, as the clone was destroyed, change the attack: send a spectre without form to the laboratory to kill Jeremy. Ulrich is fighting against X.A.N.A.-Sissi, and eventually both are devirtualized with their swords. The spectre enters into Jeremy's body and tries to drown the boy, but Aelita deactivates the tower just before Jeremy dying.
When they return to Kadic, it's night, and Jim punishes them for being out of the academy at that time. The gym teacher said Aelita, Odd and Ulrich have two hours of punishment, but Jeremy will have 6: 2 for being out of the academy and 4 for skipping classes. The next day, the four Lyoko-Warriors are in the library punished and doing homework. Jeremy's laptop starts ringing: the new Skidbladnir is ready for being able to use the next time they go to Lyoko.