Airdate: January 14, 2011
Master Wu awakens in the Underworld, and starts looking for Lord Garmadon. Meanwhile, Cole, Jay and Zane reach the Fire Temple to look for Kai and Master Wu. The temple opens up to reveal Kai and Nya sitting on top of the Fire Dragon. Kai explains to the other ninja that they became allies after the dragon realised that they were trying to protect the Golden Weapons. Nya then tells them that dragons can cross into the Underworld. Cole claims that there is no room on the Fire Dragon for all of the ninja, which leads to them recruiting the other three dragon guardians.
The ninja successfully cross over into the Underworld and try to sneak past the Skulkin by using the stalactites from the ceiling. However, they find themselves hanging on the legs of a Giant Spider, which causes them to fall and alert the Skulkin of their presence. With no way out of fighting all the Skullkin and the giant spiders, Jay exclaims they should use the Tornado of Creation.
Master Wu soon finds Lord Garmadon, who commands Samukai to attack his brother. After defeating the Skulkin, the ninja rush to the scene only to witness Master Wu losing to Samukai. Samukai takes all four Golden Weapons and announces his betrayal of Lord Garmadon. However, their sheer power causes him to be destroyed, creating a portal out of the Underworld in the process. Lord Garmadon steps through it, leaving the Golden Weapons behind, which are then picked up by the ninja. Master Wu warns them that Garmadon will return someday. Back at the Four Weapons Blacksmith, the ninja return safely to find Nya waiting, and everyone celebrates their temporary victory.
This episode contains examples of:
- Batman Gambit: Garmadon not only expected Samukai to betray him, he counted on it—Samukai's demise and the combined power of the Golden Weapons creates a portal to the Realm of Madness, allowing him to escape the Underworld and begin harnessing the dark energy needed to survive wielding the combined power of the Golden Weapons.
- Bittersweet Ending: The ninja claim the Golden Weapons, but Lord Garmadon escapes the Underworld.
- Chekhov's Classroom: In the first two pilot episodes, Wu claimed on two separate occasions that the combined power of the Golden Weapons was too much for anyone to handle. This causes Samukai's demise at the end, and it's later revealed that this forms a major part of Lord Garmadon's plannote .
- Chekhov's Gag: Inverted. The destructive power of uniting the four Golden Weapons is showcased as a plot point in the episode (creating an explosion that outright dissolves Samukai from existence), but it's later used as a throwaway gag by way of the ninja using the Weapons to high-five each other, creating a small blast that knocks them apart.
- Continuity Nod: When Jay meets Nya in person, he asks her in a strangled voice if she likes blue, which is the same question that he posed to Kai in "The Golden Weapon". Nya answers yes, causing him to pump his fist in delight.
- Dragon Rider: The Ninja use the dragons to enter the Underworld.
- Forbidden Chekhov's Gun: The Tornado of Creation, which the Ninja use to create a skeletal Ferris wheel.
- Good All Along: The dragons realizing that the ninja were only trying to protect the Golden Weapons causes them to ally with the ninja, allowing them to access the Underworld.
- Killed Off for Real: Samukai is vaporized by the combined power of the Golden Weapons, making him the first major character to die in the series.
- This Is Something He's Got to Do Himself: The ninja stumble upon Master Wu fighting Samukai, both of which are wielding the Golden Weapons. The other three move forward to help him, but Kai holds them back, telling them that "this is Sensei's fight".
- The Power of Creation: The ninja combine their individual elemental Spinjitzu tornados into one big tornado to form the Tornado of Creation. While it doesn't "create something out of nothing" as shown by the amount of debris that it sucks up, it builds a skeletal Ferris wheel that imprisons the Skulkin within its carriages.
- The Resenter: "You! You were always his favorite!"
- Why Did It Have to Be Snakes?: Cole’s afraid of dragons.
