Synopsis
The Galman Empire is destroyed but the planet Galmania is not, by a chance collision of galaxies. The Bolar Federation worlds including Planet Bolar are destroyed. The Yamato, back under the command of Captain Okita (who was cryogenically frozen after his apparent death in the first season), encounters the planet Denguil too late to save its humanoid civilisation from being flooded by the water planet Aquarius. The surviving Denguil, a warrior race who believe only the strong should survive, plan to use Aquarius to flood Earth and destroy humanity, in order to create a new home for their race. When all seems lost, the Denguil are destroyed by Desslar and the remains of his people (in gratitude for the human crew's having honored the former Gamilon leader dead earlier in the film), and the Yamato is filled with tritiated water and detonated like a giant hydrogen bomb by Okita to divert the water stream. A great deal of time is taken at the end of the film showing the fragments of the Yamato repeatedly "sinking" beneath the waves in space, Okita going down with his ship. The unedited version also shows Kodai finally marrying his longtime sweetheart Yuki (and subsequently "consummating" their marriage).
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