A group called the New Ninja appear in Ninjago City, fighting vengestone smugglers. The ninja team has lost faith and broken up. Nya roams the Endless Sea as a water dragon but begins to recover her memories. She meets a water elemental named Nyad, who helps her to find her way back home. The ninja reunite and uncover a secret shipment of vengestone in a subway tunnel. They are forced to fight Miss Demeanor and her thugs, but are humiliated when the New Ninja defeat the villains. 

A year after Nya's sacrifice, the ninja meet to investigate a vengestone smuggling operation. 

After saving a sailor from drowning, Nya meets another water elemental and hatches a plan to regain her humanity. 

The ninjas investigate the vengestone, but end up fighting among themselves, following a humiliating rescue by the New Ninja. 

When the mayor refuses to free Aspheera from Kryptarium Prison, the ninja decide to take matters into their own hands and do it themselves. 

The ninja go on a chase to retrieve the staff, but a new encounter with the New Ninja betrays their identity. 

The ninja fight the New Ninja while Aspheera helps Nya regain her human form. A new villain prepares a bad move. 

The ninja are in prison and Lloyd is visited by a mysterious masked visitor who gives him a message from the Crystal King. 

The ninja stumble upon an old enemy in prison and try to prevent his escape while Nya finds reason for hope. 

Nya frees the ninja as Samurai X. Ninjago's toughest sheriff, HoundDog McBrag, enters the arena, fired up. 

A singer on her way to Ninjago City helps Kai, Zane and Dareth escape HoundDog McBrag. Zane understands that all emotions matter. 

The ninja reunite at Twitchy Tim's gas station, escape HoundDog McBrag and decide to infiltrate the Council of the Crystal King. 

Lloyd, in disguise, infiltrates the council of the Crystal King, where he discovers who is hiding behind the kabuki mask. 

Harumi tells Lloyd her story of how she came to serve the Crystal King. 

HoundDog McBrag impounds the Destiny's Bounty while the ninja are ambushed by Crystal Spiders which blow up the subway tunnel. Lloyd shows hints of his Oni side. 

The Crystal Council attack the monastery to steal the Weapons of Spinjitzu and fight Wu, Nya, Skylor, and P.I.X.A.L. Meanwhile, the trapped ninja search for a way out of the tunnel.

The Crystal Council performs a ritual to crystalize the Weapons of Spinjitzu and awaken the Crystal King, while Nya frees the ninja from the subway tunnel. 

The Crystal King gives the Crystal Council new powers and makes his temple airborne. He gives Lloyd a chance to join his side, but Lloyd declines and escapes with Harumi. 

Lloyd and Harumi make their way through Primeval's Eye while the Crystal Council searches for them. The ninja retrieve their vehicles from the impound and manage to find and rescue Lloyd. 

The ninja clash with the Vengestone army only to have their vehicles drained by the crystals. Lloyd and Wu track down warnings of this event, which lead them to Garmadon. 

Garmadon tells Lloyd and Wu about his recent journey of self-improvement, having learned compassion by caring for a plant he named Christofern.

As Garmadon tries to teach Lloyd how to master his Oni form, Wu theorizes there is an opposite Dragon form and reaches out to Misako for research. Meanwhile, P.I.X.A.L. upgrades the ninja's vehicles to withstand the power of the crystals. 

The ninja drive through Ninjago City in their new vehicles and clash with the Crystal Warriors. Meanwhile, Wu faces the Crystal King but is unable to prevent him from unleashing a powerful weapon that crystalizes Ninjago City. 

Sensei Wu parachutes after being blown away from the Crystal Temple and is rescued by Nelson and Antonia. Jay and Nya escape the wreckage of the Destiny's Bounty. 

Lloyd and Garmadon escape HoundDog McBrag by going into the sewers where Lloyd saves McBrag from a crystal-infected Serpentine. Misako confirms that the Dragon Form exists. P.I.X.A.L. finds a broken Zane, who has returned to his Ice Emperor persona due to his damaged memory.

Skylor saves Kai and Cole from Pythor and they take shelter in an arcade where they run into Jake. Meanwhile, Lloyd and Garmadon search for their potential Serpentine allies. 

Kai and Skylor bond over cooking for refugees. The ninja re-establish communications and decide to reach out to all their allies for help. Cyrus Borg provides Ronin's fugitives with mechs and fixes Zane before P.I.X.A.L. restores his memory with an emotional outreach. 

Racer 7 drives Cole across Ninjago City to help the civilians and broadcast a distress signal to Shintaro. Meanwhile, Lloyd gives Garmadon a chance to prove he has changed. 

The ninja prepare to make their last stand against the Crystal Army as Lloyd and Garmadon plan to ambush the Crystal King. However, Garmadon fears that Lloyd does not trust him. 

Lloyd and Garmadon fight the Crystal King while the ninja strike back at the Crystal Army with old allies and new powers. 

The ninja show their true potential and perform a selfless act to save Ninjago from the Crystal King.