A top-secret government plan to utilize the dead for military purposes called U.D.S., Undead Soldier is thrown into darkness by some unknown entity. A year later, the city becomes ravaged by zombies. Three of the best AMS agents are sent in: Stick Breitling, Linda Rotta and Rikiya Busujima. They are sent out to eliminate the enemy and track down the mysterious leader of this attack, known only as "Zed". After battling through the city, they eventually confront Zed, who reveals that Stick's father was involved in project U.D.S. Zed wants revenge for his parents, who were murdered as part of the project. He despises all humans and wishes to turn them all into zombies by spreading the virus. Zed unleashes a powerful U.D.S. inside of him that he calls the God of Destruction, that he plans to use to destroy the rest of the humans, before the three agents defeat him and save humanity.