Having temporarily stalled Viral and Thymilph in the last skirmish, the Team Gurren and their newly arrived allies join forces as "Team Dai-Gurren" and launch a decisive strike against the regrouping Gunmen force.

Nia true identity is revealed, as she flaunts her authority to get rid of another one of the Four Divine Generals, Adiane. The members of the Great Gurren Brigade are now suspicious of Nia and her true intentions, but she is only concerned about the depressed Simon. Adiane later returns to finish them all off, with Lordgenome's blessing.

During the following seven years, a new civilization rises and prospers under Simon's leadership. However, these peaceful times come to end when the threat mentioned in Lordgenome's last words starts to reveal itself.

At last, Simon and Nia are reunited, and by combining the power of its members, Team Dai-Gurren creates the galaxy-sized Tengen Toppa Gurren-Lagann, and engage the Anti-Spiral threat in a decisive battle to determine the fate of the universe.