Abusive Precursors: While it's been there throughout the series and was already more or less confirmed by Red Noah itself in Episode 31, Gargoyle and Nadia's scenes aboard Red Noah really underscore how much the ancient Atlanteans were collectively a culture of assholes.
Alien Invasion: A unique variation in that the invasion actually already occurred 2 million years before the events of the series (when the Atlantean refugees landed on Earth and took control). Otherwise, Gargoyle unleashing Red Noah and instilling terror upon the land with its weaponry plays out like a basic invasion scenario.
Alien Non-Interference Clause: Averted in the series backstory when the ancient Atlantean refugees made their emergency landing on Earth. They had no compunctions whatsoever about interfering in the evolutionary development of Earth’s native species or enslaving them to rebuild their great civilization.
All Myths Are True: The Biblical Adam is revealed to have been the first artificial human created by ancient Atlantean genetic engineering. Being a prototype, Adam was the size of a giant — which indirectly implies he and other early humans were also the basis for the stories of the Nephilim.
All There in the Manual: While the broad strokes are given early in the episode, the Nadia Audio Drama CD provides a more detailed dramatization of the Nautilus survivors' travels and the refitting of the N-Nautilus between Episodes 22 and 36.
Art Evolution: Gargoyle's original character model is retired in favor of a more authentic ancient Atlantean outfit. The other Neo-Atlantis minions also discard their old uniforms in favor of new looks.
Big Damn Heroes: The N-Nautilus descending from the skies above Paris to stop Red Noah from nuking London.
Bookends: Nadia opens in Paris and the series climax likewise kicks off in the City of Lights.
Break Out the Museum Piece: The N-Nautilus is a leftover space-craft from the original Atlantean voyage to Earth 2 millions years ago. It's been buried under Tartessos since the fall of ancient Atlantis 12,000 years earlier and the crew had to excavate it and bring it up to speed (as was also established in the previous episode).
It's also explicitly confirmed the original Nautilus was similarly a surviving ancient Atlantean spacecraft that they rebuilt into a submarine.
Broken Masquerade: With his endgame commencing and Nemo (seemingly) dead, Gargoyle sees no further reason to maintain the Secret War. He shatters the Masquerade by having Red Noah appear above Paris and Emperor Neo transmit a holographic ultimatum all over the planet.
Drunk on the Dark Side: Throughout the series, Gargoyle's been taking generous sips from the chalice, so to speak. But this episode begins the shift into full-on roaring drunk for the remaining episodes. The shift is justified in-universe, as recovering Red Noah and the Blue Waters (and Nemo's presumed death at Tartessos) means Gargoyle has effectively won. So, that certainty of victory is eroding what modicum of restraint he had on his megalomania and will lead to instances of Bond Villain Stupidity in the final episodes that Gargoyle wouldn't have made earlier in the series.
Gargyole and Electra's Info Dumps regarding humanity's true origin. The ancient Atlantean refugees were too few in number to rebuild their civilization on Earth on their own. So, genetic engineering was employed to remake humanity into a viable servant race and remade in their creator’s images. This sets up the big reveal in Episode 39 about the fate of the original biological Atlanteans.
When Nadia continues to reject Gargoyle's arguments, he tells her that the time has come for her to assist them. We'll find out in the climax of next episode what he's talking about here.
Go-Go Enslavement: Nadia has been clothed with a purple Neo-Atlanten combination. Played with, though, as this new outfit is more modest than her circus outfit.
He's Back!: Downplayed example. Nemo never left the fight or lost his resolve, but Jean returning his hat (after being entrusted with it when the old Nautilus went down) underscores that Captain Nemo is finally back and ready to set sail on one last voyage.
Internal Reveal: Gargoyle learns Nadia has encountered Irion while with Nemo. He seems genuinely surprised she knows of the Whale.
In Your Nature to Destroy Yourselves: Gargoyle adopts this talking point after revealing the truth of humanity's origins to Nadia. He argues that humanity is inherently unruly and that it will destroy itself unless Atlanteans take the wheel again and provide enlightened leadership.
Nadia then correctly counter-argues that the ancient Atlanteans themselves fell victim to this trope. They destroyed themselves and their great city throughout infighting, whereas humanity’s managed to outlive and thrive without the Atlanteans. Garogyle naturally ignores the hypocrisy and dismisses her counterargument.
Kill Sat: As Red Noah is equipped with a Tower of Babel, the Slave Stars are once again put back in play for Neo-Atlantis. Gargoyle actually uses the satellites during Neo's ultimatum speech to have the Light of Babel circumvent the globe and show their power simultaneously to all of humanity.
Line in the Sand: Nemo does this before departing for the final battle. It's easier to list the people who don't cross the line and join him: the seriously wounded, one nurse to tend to them, Ayerton, Marie, and King.*
Mid-Season Upgrade: With access to the N-Nautilus repair bays, all the damage the Gratan has wracked up since Episode 21 is finally patched up. Hanson also takes advantage of the refit to upgrade the Gratan with Atlantean technology for the coming final battle.
Never Found the Body: In a contrast to Episode 21 (when he was suspicious the Nautilus had actually sunk in Episode 15) Gargoyle actually believes Nemo is truly dead this time after nuking Tartessos. It's justified, as he believes he's won and is now Drunk on the Dark Side. That being said, he's more resigned and annoyed than shocked when Nemo does turn up alive again.
No One Could Survive That!: Given the power and size of the nuke they dropped in Tartessos, Gargoyle's people (incorrectly) conclude the N-Nautilus blew up with it.
Once More, with Clarity: Various moments from throughout the series, from Irion the Whale to the old Nautilus Craftsman's Plate, are revisited as the full context behind their links to Atlantean history are clarified and resolved. Nemo's holographic family portrait is also replayed when Nadia realizes Neo was the young boy in the photo.
"Save the World" Climax: 36 episodes ago, this was a show about a pair of teenagers being pursued across Europe by a trio of jewel thieves in a funny steampunk tank. Now, with 3 episodes left, said teenagers and thieves are at the center of a battle for the fate of the entire planet and humanity itself.
Screw This, I'm Outta Here: The entire population of Paris after Red Noah appears. By the time Gargoyle makes good on his ultimatum threat, the city's deserted.
Shoo Out the Clowns: The non-combat personnel like Marie, King, and Ayerton are all left behind as the N-Nautilius prepares to take the fight to Red Noah. It's also deliberately averted with the Grandis Gang this time around, as they eagerly volunteer for the final assault.
Stock Footage: Several of the shots of the Light of Babel are taking from Episode 07.
Suicide Mission: Nemo fully expects this final confrontation with Gargoyle will be one and tries to dissuade his crew, the Grandis Gang, and Jean from following him into battle. Apart from non-combat personnel (like Marie) and injured crewmen, everybody ignores him and still volunteers.
Surprisingly Realistic Outcome: Late 19th Century Earth vs. a secret society wielding a miles-long alien battleship with ancient weaponry that can crack a planet. Earth is screwed and has no way or means of resisting such power and force. It'll take something from the world of Atlantis to stop them — something like the N-Nautilus.
Take Over the World: This has been Gargoyle's ultimate goal from jump, but gaining access to Red Noah now makes his dream a feasible reality.
Two Scenes, One Dialogue: Nadia and Gargoyle on one side, Jean and Electra on the other side, are having the same discussion about mankind's origins.
The Unreveal: Neo's confession that he didn't kill Nadia and let her escape their homeland 13 years ago is the closest we ever get to a resolution of one of the show's big mysteries: How did the infant Nadia survive Tartessos (let alone who sold her into the Circus).
Uplifted Animal: Humanity’s origins are revealed to be this. When the ancient Atlanteans crash-landed on Earth 2 million years ago, they sought to engineer a servant race to offset their low population numbers. Whales were the initial test run, but were ultimately deemed unsatisfactory. The Atlanteans then moved on to primates with more successful results. The Atlantean genetic engineers also tweaked it so that the modified humans would more closely resemble their creators. Electra even explicitly states that Atlantean genetic engineering is the in-story explanation for the evolutionary missing link between primates and humans.
This revelation’s also revealed to be one of the cornerstones of Gargoyle’s bigotry and Atlantean supremacy ideology. As Atlanteans are for all intents humanity’s creators, Gargoyle feels we’re nothing more than intelligent animals who will run amok unless a firm hand bring them into line.
Wham Line: Neo stating he's inherited the Blue Water from his Father, thus confirming (to Nadia and the audience) that he is her missing brother.
