The ninjas travel to attend the birthday party of Princess Vania, in the distant Kingdom of Shintaro, and bring along Master Wu.
The ninjas are welcomed to Shintaro, where Cole and Princess Vania investigate a mysterious visitor and explore a secret underground mine.
The ninjas attempt to rescue Cole, but the bickering of his fellow prisoners alerts the Skull Sorcerer, and soon the ninjas are prisoners too.
In order to escape the Skull Sorcerer's chain gang, the ninja must convince the Munce and Geckles to put aside their distrust and work together.
Separated from the others, Nya, Jay and Lloyd follow a Munce named Murt deep into the mountains, where they meet the Munce Queen.
Kai and Zane discover a party of Geckles, who suspect them of working with the Skull Sorcerer and bring them to their leader, Chancellor Gulch.
Cole must trust his instincts and make the right choices to find his way to the surface and alert King Vangelis of the dangerous Skull Sorcerer.
Princess Vania tries to catch the falling Master Wu and Cole. But with too much weight on her wings, they find themselves plunging into the mountain.
Having survived their fall into the mountain, Cole, Wu and Princess Vania befriend a motley group of survivors called the Lowly.
Cole leads the Lowly, Princess Vania and Master Wu in a series of fruitless efforts to find a way out of the inescapable Rock-Bottom.
Nya and Kai attempt to bring the Munce and Geckles together in an effort to defeat their mutual enemy, the Skull Sorcerer.
Pursued by a magma monster, Cole, Princess Vania, Wu & the Lowly arrive at a mysterious temple deep in Shintaro Mountain.
The ninjas, the Munce and the Geckles take refuge in the Geckle Strong-Cave after they're all forced to flee by the Grief-Bringer's arrival.
Cole, the Lowly, Princess Vania and Wu learn that the stone-mech is powered by Elemental Earth energy and use it to blast their way out of the mountain.
Cole and the Upply arrive at the Skull Sorcerer's Keep and find the ninjas locked into cages and the Geckles and Munce back at work in the chain gang.
As Cole and the Skull Sorcerer face off, the Geckles and Munce storm the Keep. Plundar frees the ninjas from their cages so they can join the battle.
Watch Ninjago: Masters of Spinjitzu Season 13, Episode 4: The Two Blades online on FlixGems. In order to escape the Skull Sorcerer's chain gang, the ninja must convince the Munce and Geckles to put aside their distrust and work together.