When Nya's powers are disrupted, the Ninja set off in search of answers and find themselves at the bottom of endless oceans where they discover that her powers are linked to an ancient mythical creature.

Season 15 Episode 4 - Five Thousand Fathoms Down

Nya and Maya use underwater suits to travel to an ancient temple after they realize its power source is the only way to get the Hydro Bounty running. Air Date : 11th-Apr-2021

Season 15 Episode 1 - A Big Splash

The ninjas ambush a new villain named Miss Demeanor. Nya creates a water cyclone to stop her but loses control of it, threatening a nearby village. Air Date : 4th-Apr-2021  Read More

Season 15 Episode 2 - The Call of the Deep

Maya attempts to take charge of Nya's life to solve her problems. Zane and Pixal respond to a distress call at sea. Air Date : 4th-Apr-2021  Read More

Season 15 Episode 3 - Unsinkable

Nya, Jay, Zane, Pixal and Lloyd board a new submarine, the Hydro Bounty, and set off to find the source of the energy signal disrupting Nya's powers. Air Date : 11th-Apr-2021  Read More

Season 15 Episode 4 - Five Thousand Fathoms Down

Nya and Maya use underwater suits to travel to an ancient temple after they realize its power source is the only way to get the Hydro Bounty running. Air Date : 11th-Apr-2021  Read More

Season 15 Episode 5 - The Wrath of Kalmaar

Nya and Maya attempt to get out of a tough predicament. Meanwhile, Jay risks his life while trying to restore power to the Hydro Bounty. Air Date : 18th-Apr-2021  Read More

Season 15 Episode 6 - Long Live the King

After Nya and Maya's rescue, the ninjas are escorted to Merlopia to face King Trimaar. However, a betrayal turns the ninjas into fugitives. Air Date : 18th-Apr-2021  Read More

Season 15 Episode 7 - Escape from Merlopia

The ninjas survive the palace flooding — but are pursued by ripper sharks. Benthomaar comes to help and leads them to the hangar bay. Air Date : 25th-Apr-2021  Read More

Season 15 Episode 8 - The Tale of Benthomaar

A flashback tells the tale of Benthomaar, revealing how King Trimaar finds him as a baby and raises Benthomaar as his own. Air Date : 25th-Apr-2021  Read More

Season 15 Episode 9 - The Storm Amulet

The ninjas return to the island of the Keepers and ask their leader to keep an amulet safe in Ninjago City — but they make a surprising discovery. Air Date : 2nd-May-2021  Read More

Season 15 Episode 10 - Riddle of the Sphinx

Kai, Ray, Cole, Wu, and Misako receive Nya's warning and rush to the Explorer's Club. Benthomaar encourages Nya to use her power in a surprising new way. Air Date : 2nd-May-2021  Read More

Season 15 Episode 11 - Papergirl

As Kalmaar and the ninjas wage a battle in Ninjago City, the storm amulet ends up in the possession of a determined paper girl. Air Date : 9th-May-2021  Read More

Season 15 Episode 12 - Master of the Sea

Benthomaar tells Nya the tale of Nyad. Meanwhile, Master Wu, Kai, Cole, Ray, and Misako try to keep Kalmaar from taking off with the storm amulet. Air Date : 9th-May-2021  Read More

Season 15 Episode 13 - The Calm Before the Storm

The doomsday serpent, Wojira, rises from the sea. In Ninjago City, Glutinous emerges from the water with a dire warning. Air Date : 16th-May-2021  Read More

Season 15 Episode 14 - Assault on Ninjago City

The ninjas leap into action after Kalmaar and Wojira arrive in Ninjago City, bringing a tsunami that floods the entire city. Air Date : 16th-May-2021  Read More

Season 15 Episode 15 - Nyad

Overpowered by Wojira, the ninjas retreat to the NGTV building to regroup. Nya might make a decision that she may never be able to come back from. Air Date : 23rd-May-2021  Read More

Season 15 Episode 16 - The Turn of the Tide

Kalmaar's temper proves too much for Wojira to handle during battle while the ninjas try to help Nya fulfill her destiny. Air Date : 23rd-May-2021  Read More