As Gamilans face a dire crisis with their dying planet, Aberdt Desler devises a daring plan to save his people by pretending to bow to the oppressive regime of planet Galman. His true intention is to overthrow the rulers and hasten his nation's relocation. However, a mysterious colossal force disrupts their migration and transforms their twin planet, Iscandar, home to Queen Starsha. Meanwhile, on Earth, festivities abound for the valiant Space Battleship Yamato and its gallant crew. With a fresh wave of skilled recruits under the command of Yuki Mori and Shirou Sanada, disagreements arise over Captain Susumu Kodai's previous choices. Amidst a six-month training voyage and diplomatic exchanges with the Gamilans, news of the disaster reaches the crew. Against all odds, Kodai steers the fleet towards Iscandar to assist the stranded survivors, defying direct orders.