No sooner has Gurren Lagann managed to dispose half of the Mugann attcking the Arc-Gurren than an energy blast from the moon is fired.Gurren Lagann stops it with a giant drill. It then uses its wings as a boomerang to destroy the cannon before it can fire again. When more cannons show up on the moon's surface to fire at Gurren Lagann, Simon has to use a long drill to catch the cannons' energy to destroy them.
When the two large Mugann separate to surround the Arc-Gurren and Gurren Lagann, Simon reminds Rossiu how they have managed to pull through before. Leeron recalls that the Arc-Gurren is a gunmen like Teppelin, Simon, along with Viral, powers up Gurren Lagann to escape the large mugann and combine with the Arc-Gurren. The vessel transforms into the Arc-Gurren Lagann, which punches the two large mugann, now combined into one enormous mugann, into a hole in the space-time continuum. However the moon is still falling as a huge face can be seen on its surface
To Simon and Viral's surprise, the biocomputer that was Lordgenome, knocked out earlier, awakens to reveal that the moon is his old flagship Cathedral Terra. Lordgenome then explains that inserting the source of Simon's Spiral power can enable him to control the moon. Reaching the core of the moon, Gurren Lagann is about to insert its drill when Nia the messenger of the Anti-Spirals stands in its way. Drilling through her would cause an explosion (since she's made of the same matter as the mugann) that would destroy the control system. This, Nia says, is Absolute Despair, for in order to quell spiral lifeforms' survival instincts the best deterrents are despair and terror, but Simon counters that they've stood up to difficult and hopeless situations and emerged stronger. This, he says, is why he's here. Realizing that because Nia still wears the engagement ring he gave her, she wants Simon to save her in spite of her claims to the contrary.
Nia gets out of the way as Gurren Lagann plunges its Giga Drill into the hole, stopping the moon from falling and in the process it transforms into a gigantic vessel that dwarfs the Arc-Gurren Lagann: the Cathedral Terra. Now that the Human Annihilation System has been deactivated, the Anti-Spirals will recall Nia to their homeworld. Nia (having resumed her original personality) asks Simon if he'll come for her. Simon promises to do so, then Nia disappears.
As the Arc-Gurren Lagann returns to Kamina City, Rossiu realizes that he's no match for Simon, who has managed to overcome whatever obstacle in his path.
Tropes in this episode:
- "I Know You're in There Somewhere" Fight: Simon notices that the engagement ring that he gave Nia is on her finger.He then realizes that despite her cold outer persona, the Nia he knows and loves wants him to help her.
