Doctor Saotome carries out his diabolical plan of revenge against the human race, thwarted by an indomitable Ryoma, who is soon joined by the other two members of the Getter team, Musashi and Hayato. From the capsule of Saotome emerges a mysterious young man, Go, to the great satisfaction of Saotome who manages to take refuge inside his laboratory. Ryoma and Hayato, despite the mutual hatred that has characterized their relationship since the death of Saotome, chase the revived scientist, facing in the base some monsters shelled by other capsules identical to that of Go. The power of the Getter rays triggered in the battle contaminates the battle territory and Dr. Saotome brings in the mighty Shin Getter Robot. Meanwhile Cowen and Stinger begin plotting to take control of the United Nations Security Council.