This article needs to be built up. This article lacks substantial content. You can help Brickipedia by "adding on some bricks." In other words, it needs to be expanded. After you expand the article, please remove the "Expand" template. Further information might be found on the talk page.
P.I.X.A.L. brings Wu and the Ninja to the Ninjago City Docks and raises the Hydro Bounty, a vehicle she has been working on for some years. Nya, fearing that her powers may once again misfire while on the journey, wonders if she shouldn't accompany them. Jay reassures her, and Wu reminds her that the alternative is staying at the Monastery of Spinjitzu with her mother. Quickly agreeing, Nya informs Maya and Ray, the latter of whom will be staying at the Monastery with Cole, Kai, and Wu. Maya expresses her own doubts that Nya should be going, but Nya asserts that this is how she handles being the Master of Water.
P.I.X.A.L., Zane, Lloyd, Zane, and Jay board the Hydro Bounty, with Zane-adopting pirate mannerisms in the same way he previously took on a detective persona-set sail for the Tartarus Trench. In transit, the group come across mysterious occurrences that point to the presence of a stowaway. This proves to be Maya (rather than a ghost butler named Ducklesworth as Jay proposes) much to Nya's annoyance. Too far out to take her back, the crew-with varying degrees of enthusiasm-welcomes her aboard as they enter a ships' graveyard.
They are then attacked by a large manta ray equipped with torpedo launchers, which cripples the Hydro Bounty with its attacks. Nearing crush depth, the group manages to land the sinking ship on an undersea ledge, fortunately satisfying their assailant that they have been destroyed. Unfortunately, the Bounty's systems have been badly damaged, leaving them stranded in the ocean's depths.
Spoilers end here.
Cole's comments about not calling a ship unsinkable are presumably a reference to the RMS Titanic.