The distant future. For hundreds of years, people have lived underground, living in fear of earthquakes and cave-ins that happen from time to time. Simon, a boy who had been digging new tunnels to expand his village, comes across a small drill that glows mysteriously.Kamina, Simon's surrogate older brother, believes in the existence of a "surface" world above and has been scheming to escape there.

Kamina and Simon destroy the Gunmen that attacked Giha Village and make it to the surface. What they find is a world where even more Gunmen lay in wait for them.The pair visit Littner Village, where Yoko lives. There, the villagers fight Gunmen every day like clockwork.

Kamina, in a joint operation with Simon, takes control of an impressive Gunmen and destroys the enemy. Yoko goes out to hunt, and invites along a boastful Kamina, who has named his stolen Gunmen "Gurren". At her hunting spot, Kamina exchanges blows with a Beastman, who calls himself Viral.Lagann and Gurren retreat in the face of the might of Viral's Gunmen, Enki.

During the brutal battle, Kamina and Simon pull off a miraculous combining maneuver with Lagann and Gurren to form "Gurren Lagann" to defeat Viral. Elated by their victory, they set out on a journey to try to reach the enemy's stronghold; however, Kamina suddenly declares that they're going to have a crash course in combining almost immediately after they leave.

Kamina and company come to terms with the Black Siblings and continue on their journey. As soon as they arrive at a nondescript spot, the ground beneath them suddenly gives way and they fall underground, Gunmen and all.They find themselves in an odd village where they worship a crumbling Gunmen as a "Face God".

Adding Rossiu, Darry, and Gimmy to their little band, the heroes continue their journey to the enemy's stronghold, when suddenly a force of Gunmen suddenly appears, blocking their path. Having grown stronger over the course of their battles, Kamina and the others easily overtake the enemy force, but one gets away.

After Kamina and the group successfully thwart the wolf Beastman's trap, the Beastman Viral appears before them. He has come for a rematch to vindicate his honor having been defeated in the previous battle and his helmet - the embodiment of his warrior's pride - stolen from him. A fierce battle unfolds between Gurren Lagann and Enkidu.

During the battle against the fortress Gunmen Dai-Gunzan, it is Littner Village's Dayakka and Kittan along with the other members of the Black Siblings who come to Gurren Lagann's rescue.Following Kamina's example, they have been stealing Beastmen's Gunmen and making them their own.

Word reaches the Capital of the death Thymilph, one of the Four Generals. However, the battle was nothing more than the opening salvo of the new conflict ahead.At the end of the fierce battle, Team Dai-Gurren held the Dai-Gunzan in their control; however, the price they paid for their prize was all too high.

The members of Team Dai-Gurren are unable to conceal their shock when they learn the identity of Nia, the girl Simon brings back with him. They unsuccessfully try to interrogate her for information on the enemy and foist her off on Simon to get her out of their hair. Simon, who is still unable to recover from the loss of Kamina, is asked about him by Nia.

Team Dai-Gurren manages to drive off Adiane. However, Simon still hasn't recovered and shuts himself in his room. Everyone gives up on him, except for Nia, who continues to feel concerned for Simon.Dai-Gurren receives an emergency transmission as they make their way to the Capital.

Simon foils Guame's sneaky trap and finally snaps out of his funk.Taking up Kamina's mantle, Simon sets his sights on the Royal Capital of Teppelin as the new leader of Team Dai-Gurren.As they advance, they are stopped by a vast sea stretching out before them.

Simon's Team Dai-Gurren emerges victoriously in their naval battle against Adiane the Elegant, one of the Four Generals. While Team Dai-Gurren sets course for Teppelin before the echoes of the battle have a chance to fade, Nia suddenly makes a request that she would like to be put to work.

A month has passed since the battle with General Cytomander the Swift, and at long last, Team Dai-Gurren is within a stone's throw of Teppelin, the Royal Capital.Without a moment's rest, the operation to invade Teppelin begins with a bang with the Four General flagships Dai-Gundo and Dai-Gunten stand in Team Dai-Gurren's way.

Teppelin begins to crumble away in front of Simon and the others, who have defeated two of the Four Generals, Guame and Cytomander. The city itself turns out to be a titanic Gunmen and as the members of Team Dai-Gurren stare on, dumbfounded, Gurren Lagann soars in the heavens as if pulled towards it. There, sitting on a throne is the Spiral King, Lordgenome.

A long journey that began with two men, Simon and Kamina, breaking through the surface from the underground village. A meeting in the depths of despair, a journey to an unknown world, new friends, and a farewell. The "Compilation Episode" weaves together all of these pieces to tell the story.

Seven years have passed since the battle of Teppelin. Set free onto the surface, humanity is now rapidly building a civilization based on technology left behind by the Spiral King - even launching a probe Gunmen to the Moon. Amidst all this, some have gotten married and had children, while some have set out on a journey to make a fresh start.

Exactly as Lordgenome predicted, a weapon of unknown origin appears the instant the number of humans living above ground reached one million. And the person who issues the declaration of war against humanity is someone that Simon and the other never could have imagined - Nia.Simon having barely managed to repel the enemy's attack, wanders Kamina City hoping to find Nia to learn what is going on.

When Simon returns from driving off the Mugann, he is placed under arrest by Rossiu and put in solitary confinement. Though initially angry, the members of Team Gurren can't disagree when Rossiu declares that this is the only way to appease the citizenry, who have taken to the streets to riot over the battle within Kamina City and the news of the impeding lunar impact.

In prison and put on death row, Simon encounters his old rival, Viral, who is also imprisoned there.Meanwhile, Rossiu prepares for the impending dooms day by evacuating the humans on the surface and sending them underground. He also steps up the preparations to activate the Spiral King's legacy, the Arc-Gurren, hidden deep beneath Kamina City.

We rewind the clock one year… A new teacher is assigned to the grade school on Korehana Island, which is inhabited by humans who have come up to the surface. In the blink of an eye, this female teacher blends into life on the island and is beloved by all the students. Nakim, one of her students, doesn't fit in on the island and doesn't get along well with the other children in his class.

A massive formation of Mugann attacks the Arc-Gunmen in orbit as it escapes into space. Gimmy and Darry's Grapearl Squadron fights hard, but in vain, and the Arc-Gurren takes on more and more damage. Just when Rossiu and the crew of the Arc-Gurren have been driven to the brink of despair, Simon's voice rings out on the bridge."Rossiu, don't give up!

Fending off the Anti-Spiral's ferocious attack, Team Dai-Gurren snatches victory from the jaws of defeat. Before the echoes of the battle have a chance to fade, they begin their search for the Anti-Spirals' stronghold. However, it is in a universe outside normal space-time, so locating it is no easy matter. While everyone is hard at work, Rossiu turns up by himself at his birthplace, Adai Village.

To save humanity's future, as well as his beloved Nia, Simon and Team Dai-Gurren set out in the Super Galaxy Dai-Gurren in search of the Anti-Spirals' home world, located in a gap between dimensions.