After the Gauna destroyed Earth, humans found refuge on the giant spacecraft called Sidonia. Centuries later, the Gauna attacked again, but Tsumugi Shiraui, a hybrid of human and Gauna, and Nagate Tanikaze, a renowned mech pilot, led the charge and defeated the invaders. A decade passed before the inhabitants of Sidonia savored a fleeting moment of peace. It was then that Tsumugi realized her love for Nagate, who was hailed as a hero. Captain Kobayashi knew the calm wouldn't last, so they made the crucial decision to engage in one final battle that would determine the fate of humanity's last survivors. As the crew prepare for this epic confrontation, they must protect their loved ones and fight for the survival of their people. Will they overcome the deadly Gauna threat and ensure their future? Only time will tell.