While Vera adjusts to life as a virtual teenager, the Sourcerer reanimates an old enemy, advancing his mission to destroy the world.
Following his defeat by the Guardians, The Sourcerer resurrects Megabyte from Mainframe and gives him an "upgrade" changing his appearance and giving him new abilities. He then summons him to a place outside of Mainframe's outer wall where he makes first contact with the virus. The Sourcerer tells Megabyte he has injected him with a Delete Code, so the virus must follow his orders or face deletion.
Meanwhile, Austin, Parker, Tamra and Trey look for Vera, who had skipped class earlier. They find her in Room Zero, having finished fabricating and now donning a new (and random) set of clothes based on teenage fashion trends. After a brief banter, Vera tells them that they were all hand-selected to be Guardians based on their skill in the Cyber Guardians mobile game; Trey for his strength, Tamra for Stealth, Parker for Intellect and Austin for Leadership. Feeling the weight of the world on his shoulders, and a wave of jealousy from Trey, Austin quits the team and returns home, finding his mother getting things ready for a new exchange student living with them.
Back in Cyberspace, Megabyte has arrived at the UK Power Grid, where the Guardians had patched up a rift made by The Sourcerer. As Megabyte attacks the patch, Vera detects it in the real world and alerts the Guardians. All except Austin make their way to Room Zero. Unable to wait for their leader, Parker, Tamra and Trey enter cyberspace as Googz, Enigma and D-Frag. When they arrive at the Power Grid, they encounter Megabyte for the first time.
Meanwhile, Austin has visited his father's grave for some soul-searching. He confesses the weight he now feels resting on him, his fear of failure, and the possibility of letting everyone down or even losing someone. At the base of the headstone, Austin reads the words "Do what is right, and you will do no wrong." Inspired, Austin rushes back to Room Zero.
During their fight with Megabyte, Googz attempts to repair the cyber-patch over the dark code rift while the other two keep Megabyte occupied. Unfortunately, their efforts are in vain due to the Megabyte's upgraded speed and strength. Without their leader, the Guardians are easily overpowered and the virus manages to breach the cyber patch, allowing The Sourcerer's cyber-locusts to do their damage yet again.
Upon Austin's return to Room Zero, Vera chastises him for his tardiness and, at Austin's request, begins work to convert his Code Disrupter into a Cyber Sealer which can permanently close the rift. Austin then enters cyberspace as Vector.
The battle gains new momentum as Vector arrives on his zip-board. Megabyte infects one of the cyber-locusts, increasing its size and using it as a mount, and an aerial battle between the virus and Vector ensues. With his Code Disrupter unavailable while Vera modifies it, Vector has to evade Megabyte's attacks while trying to buy time. But just as Megabyte's giant Cyber-Locust is about to come down on him, Vector fires his Booster Pack in the mount's face, blinding it, and both the locust and Megabyte crash into one of the substations.
Even though Megabyte is out of commission, the battle is far from over. With no time to construct a new cyber-patch, the Guardians are quickly becoming overwhelmed by the influx of cyber-locusts. With work on his Cyber Sealer complete and only five seconds away from being deployed, Vector uses his Blink ability to slow down time and zip past the locusts. Finally, his Cyber Sealer is ready, and Vector fires it at the rift, closing it for good. The remaining cyber-locusts vanish, cut off from their source of control.
Victorious, the Guardians leave cyber-space, believing Megabyte has been destroyed. However...
"This is far from over, Guardians." - Megabyte
Austin returns home with Parker. However, they're in for a surprise as they find that Vera is the exchange student staying with them. Meanwhile, Megabyte reports back The Sourcerer, making him aware of the Guardian Code thwarting their efforts.
"This Guardian Code must not stand in the way of my plans... Eliminate it!" - The Sourcerer
- Timothy E. Brummond voices Megabyte in place of the late Tony Jay.
- This episode marks the first time:
- an original Reboot character is in direct communication with a User in this series.
- Mainframe is featured in the series.
- the next-generation Guardians face Megabyte.