Continuation of the Ginga Eiyuu Densetsu: Die Neue These series.

In the year 2201, one year after the Yamato saved Earth from radioactive contamination, a new threat emerges. The Yamato makes its final journey to save the Earth from this new threat. Earth has almost recovered from the battle against Gamilus, and reconstruction has expanded to the other planets. When former Yamato crew-mates discover a strange, garbled message that seems to be coming from a white comet headed towards Earth, they hijack their old space fortress and begin a new battle.

In the year 2199, the Gamilon race declares war on humans, intent on taking Earth for themselves. The fighters on Earth do everything in their might to keep the planet stable, but alien technology proves to be far too advanced, and the resulting destruction renders the surface of planet Earth completely uninhabitable. The underground shelters are also becoming weak, and if nothing changes, humans will become extinct in less than a year. But just when all seems lost, Queen Starsha from the planet Iscandar offers a helping hand. The key to victory lies in the Cosmo-Cleaner D, which can eliminate the radiation that Earth is suffering from. However, the only way to get a hold of this life-saving device is if someone from Earth goes to Iscandar―148,000 light years away―to retrieve it. The problem is, they have less than a year before time runs out. The fate of the entire human race lies in the hands of the crew of a salvaged WWII craft, the Space Battleship Yamato.

A year has passed since the Star Force returned to save the Earth but another danger now approaches from deep space. A gigantic White Comet hurtles toward our galaxy, obliterating everything in its path. But it is no ordinary comet—it is the deadly Comet Empire, conqueror of worlds... and Earth is the next target! Against orders, the Star Force blasts off to investigate, but even if they can get past the flagship Andromeda, they don't yet know the true nature of their new enemy!