The plot of Zombie Nation takes place in 1999, when a meteor known as "Darc Seed" (Eva in the Japanese version) crashes in the Nevada desert. Darc Seed/Eva then shoots magnetic rays and turns the people of the United States into zombies. Darc Seed/Eva also brings the Statue of Liberty to life to follow its commands. The magnetic rays also allow Darc Seed/Eva to control many deadly weapons, including the most powerful weapon of all—the legendary samurai sword Shura. The head of the samurai Namakubi hears of Shura falling into Darc Seed's clutches. He then heads to the United States to destroy Darc Seed, free the American people from the looming zombification and reclaim the samurai sword Shura.