In the year 2199, Earth lies in ruins after relentless bombardment by the Gamilas Empire, its survivors driven underground as radiation creeps toward their last shelters with barely a year left before extinction. An emergency transmission from the distant planet Iscandar offers a way to reverse the damage, so Captain Juuzou Okita retrofits the sunken WWII battleship Yamato into a starship and sets out with a young, headstrong crewman named Susumu Kodai. Alongside navigator Yuki Mori, they face the Gamilas' ruler Aberdt Desler on a voyage across hostile space to reach Iscandar in time.