The Lyoko Warriors return to Siberia in an attempt to finally free William from Xana’s clutches. Using data culled by Aelita from the last teleportation of the youth Jeremy is able to create a program to find their imprisoned friend. But in order to bring him home, our heroes will have to accomplish a multitude of tasks in synchronization—no small feat when also faced with the Kolossus… and an entire army of robots!
This episode features examples of:
- Big "NO!": Multiple, fitting for such a climactic episode:
- First said by William when Jérémie is able to use the multi-agent system to temporarily paralyze the Kolossus.
- Then by Odd and Aelita each when they are deteleported by the robots, and by Ulrich when he is crushed by the Kolossus (all three doubling as Killed Mid-Sentence) and then by Jérémie after Aelita is deteleported.
- Then by Jérémie when the Kolossus prepares to destory the Skid - with Aelita still inside, followed by Aelita when the Skid is thrashing around after being hit by the Kolossus, and finally by Jérémie when the Skid falls off the Ice floe and into the Digital Sea.
- Blatant Lies: As Ulrich and Yumi are on Lyoko and discuss William coming home again, Yumi asks Ulrich if he's going to be upset seeing him hang out with her again.Ulrich: "Uh... no. Why should I? There's no reason to. After all, we decided we were just good friends. Didn't we?"Yumi doesn't respond and looks away sadly
- Body Surf: The final time William shows up under XANA's control, and get's free by the gang too.
- Cannot Spit It Out: When learning Aelita and Jérémie worked together on Replika research the whole weekend without taking out a little romance for themselves (though Jérémie implies otherwise), Odd draws parallels between their relationship to Yumi and Ulrich's. When the latter couple give a surprised reaction, Odd calls them out on their alleged Just Friends status, when it's painfully obvious to everyone they're clearly more than friends and aren't fooling anyone. Ulrich and Yumi then turn to look at each other while blushing.
- Continuity Nod: When Jérémie comes up with the idea of creating a multi-agent program, Aelita and Odd bring up the creation of the Marabounta back in season 2 that almost killed Aelita. It was such a big threat, even XANA wanted to get rid of it and briefly allied with the warriors.
- Crying Wolf: When walking through the Siberian base, Odd and Aelita pass through an army of XANA's robots standing at attention. Odd frightens Aelita by telling her that one of the robots started moving, annoying her when he reveals he was just joking. A moment later, Odd sees the robots begin to move for real - which Aelita naturally doesn't believe until she turns around and sees the robots heading straight for them.
- Green-Eyed Monster: In the final scene, William comes back home and gives Yumi a smile and wave. Yumi smiles and waves back in return. Ulrich, watching the two, glares and gives a clearly jealous grumble.
- Death by Irony: Ulrich has William lying on the ground, defenseless, ready to devirtualize him, but his alerting Jérémie to run the program to free William gives William enough time to escape with his Super Smoke, leaving Ulrich to be crushed by the Kolossus. William, having run away to safety, smugly declares victory, before being devirtualized himself by Odd, who was standing behind it.
- Expy: With the evidence of the previous episode, the robots are very clearly based on the Cybermen, who also preserve the brain. It's possible the idea came from the then-recent episodes too, which explored the concept of preserving the brain in a cybernetic body in greater detail.
- Exact Words: Jérémie tells the other Lyoko Warriors that rescuing William is simple - they must devirtualize William at the same moment that Aelita runs their special program in the supercomputer on the Siberian base. Yumi sarcastically jokes about how simple it will be to defeat William. Jérémie responds that he said that it was simple, not easy.
- Free-Fall Fight: Ulrich and William start fighting on the Kolossus' shoulder and end up falling to the ground, but it doesn't interrupt their fight in the least.
- Robot Soldier: XANA is building an army of those in Siberia and Jérémie guesses that XANA intends to use them to enslave humanity.
