The episode opens with the ninja and Nya returning to New Ninjago City, where they find a mob of civilians acting like people from an apocalyptic movie who are lead by "The Postman"(Mailman (Ninjago). The encounter Cyrus Borg, who is no longer influenced by the Overlord and explains that the people are doing this because they're bored and have an active imagination. The ninja agree to go underground to search for the Serpentine, believing that they stole the hard drive containing the Overlord, while P.I.X.A.L. stays behind to assist Cyrus. Meanwhile, the Stranger discusses his plans with the Digital Overlord to obtain a power source for the Nindroids, while Lloyd and Sensei Garmadon make their way through Hiroshi's Labyrinth to stay hidden.
The ninja and Nya search underground for the Serpentine, eventually finding Skales outside of the Stone Army Tomb. Skales brings them inside and tells them how they have decided to adapt to a new life and become more "civilized", choosing not to become involved with any of the Overlord's plans. Acidicus then tells the group about the Curse of the Golden Master, and how there will be a being whose power will be equal to that of the First Spinjitzu Master's. The Serpentine attempted to warn people of this, but were treated as the enemy, to which they fled underground. In the meantime, Cyrus Borg meets with P.I.X.A.L. in his office, with P.I.X.A.L. telling Cyrus of her connection with Zane. Cyrus tells her that she doesn't belong to anyone, even him, and that she is fully independent. Dareth also acts as the substitute teacer for Sensei Wu's students, as they go to the city's aquariam. There, while viewing the Electro Cobrai exhibit, the Stranger arrives and shatters the tank. He obtains the Electro Cobrai while Dareth fends off a shark, saving the students. Underground, the ninja contemplate the situation until an army of Nindroids raids the tomb. The Serpentine scatter, with the ninja defending them and defeating the Nindroids by finding out that the Electrocobrai are their power source. Skales tells them at the Curse of the Golden Master is upon them, and says that they would not be able to assist the ninja because they're choosing to stay out of the conflict. The ninja then return to the surface.
As Lloyd and Sensei Garmadon continue their journey, they're attacked by the corrupt Sensei Wu and various Nindroids. Garmadon battles Wu, while Lloyd rides off on his bike. He is pursued by various Nindroids using flight gear, although he manages to evade them all before coming to a stop next to a cliff. There, the Nindroid Mechdragon rises up before him, posessed by the Overlord. Wu is holding Garmadon hostage on its back. Lloyd prepares to battle the Mechdragon, but the Stranger unleashes a snake that constricts Lloyd, draining him of his powers. The Stranger then reveals himself to be Pythor P. Chumsworth, having survived his ordeal with the Great Devourer, although his skin was turned white in the process. Pythor brings Lloyd aboard the Mechdragon, to which Garmadon is pushed off the side and into the water. The Mechdragon flies off with Lloyd, and Garmadon emerges from the water, telling his son to be strong and that he would find him.