Yoko, Will You Do Me A Favor?

At Teppelin, Cytomander needles Guame over his failed execution while the generals note Adiane's absence; she is still hunting the humans who killed Thymilph, and with an ocean between the Dai-Gurren and the capital, the terrain now favors her.

Reaching the coast, the crew learns from Leeron that their land-built ship needs refitting before it can swim, which means beach time. The men's swimsuit hopes end in disappointment with Yoko, who exposes no more skin than usual, and delight with Nia, who then infuriates Yoko further by beating her at every game on the sand: volleyball, watermelon splitting, sandcastles, underwater breath-holding, all of it. A dropped bowl of crab and a round of laughter send Yoko storming off.

The refitted Dai-Gurren sets out and is promptly torpedoed by Adiane's flagship, the submarine Dai-Gunkai, with Viral serving as acting commander. Return fire misses everything. Adiane's Sayrune rules the depths, Kittan's machine floods the moment it submerges, and only Gurren Lagann's self-sealing hull lets it keep fighting. The Dai-Gunkai shears off the ship's flippers and drags it under. As water floods the bridge, Nia alone stays calm, telling the panicking crew that Simon will come through for them. Her words reach him; goggles down, he converts Gurren Lagann's arms and head into drills, tears free of Sayrune's grip, and rockets upward, shattering Adiane's thrown wings and ramming his own ship back to the surface hard enough to rip the enemy submarine's arms away.

Adiane answers with a hostage. Sayrune leaps aboard, snatches Nia in its claws, and forces the Dai-Gurren's own cannons to train on Gurren Lagann. Nobody dares move except Yoko, who levels her rifle at the captive girl while Nia simply closes her eyes. The first shot tears through Nia's hair and misses her skull by inches; the second rips through more hair and slams into Sayrune's shoulder, springing Nia loose for Old Coco to catch. Her leverage gone, Adiane sneers that firing at such range would kill everyone, and asks if they are really so stupid. Yoko dryly confirms they are, and Attenborough gleefully delivers the point-blank salvo. Viral lunges to intervene, but Simon drills clean through the Dai-Gunkai, and Adiane whispers an apology to Thymilph as her machine detonates. The blast throws up a wave that carries the Dai-Gurren across the remaining ocean, while a battered Viral rages alone on a wreckage-strewn shore.

Afterward Nia asks Yoko to tidy her ruined hair. Asked why she closed her eyes at gunpoint, Nia answers that a rifle expert deserved her trust. Yoko calls herself an idiot for ever doubting the girl, finishes the shorter cut, and watches Nia dash off to show Simon.

Adiane dies along with her Sayrune, and the Dai-Gunkai is destroyed.

Nia earns Yoko's trust and friendship, and her damaged hair is cut short.

The Dai-Gurren completes its ocean crossing on the road to Teppelin.

Viral is briefly shown weeping amid the wreckage, an early hint of his feelings for Adiane that the manga and the second Parallel Works video develop further.

Background gags include a beastman strongly resembling Squidward from SpongeBob SquarePants and a girl in the crowd who looks strikingly like Candace from Phineas and Ferb.

The episode first aired in Japan on June 17, 2007, and in English on September 15, 2008.