Dr. Kozaburo Nambu, born into wealth with an influential businessman father owning a private airfield and bank, invested his entire family fortune into the Earth's Mantle Project and Galactor research after his parents' deaths. He deliberately severed family ties as atonement for separating his childhood friend Kentaro Washio from his wife and son. Holding executive positions at Interpol and the International Science Organization (ISO), Nambu possessed expertise spanning space engineering, physics, chemistry, astronomy, and medicine. His political acumen and fundraising skills proved vital for the Mantle Project. He designed and constructed the underwater Crescent Coral Base, focusing on ocean conservation and self-defense technology like the Bird Missiles used by the Science Ninja Team. Nambu formed the Science Ninja Team to combat Galactor, recruiting five youths and developing their bird-themed technology, Science Ninja Technique, and mecha, including the God Phoenix. He implemented a critical design requiring all five members to cooperate for activating the God Phoenix's Bird Missiles or Firebird mode, addressing their initial lack of teamwork. He became legal guardian to Ken Washio, Joe Asakura, Jun, and Jinpei after their parents died, while Ryu Nakanishi maintained ties with his biological family. Nambu concealed Kentaro Washio's survival and undercover identity as Red Impulse from Ken for years, facilitating Kentaro's infiltration of Galactor. Following Director Anderson's death in *Gatchaman II*, Nambu assumed leadership of the ISO. In *Gatchaman Fighter*, he relocated the team to the underwater Gallatown (G-Town) base and oversaw deployment of their new mecha, the Gatchaspartan, equipped with a radiation-emitting "Hypershoot" weapon usable only by Ken. Nambu was killed near the end of *Gatchaman Fighter* during Leader Z's antimatter asteroid ("Poison Apple") crisis. His death left engineer Kamo as the team's mentor, though Nambu had prepared a mysterious reincarnation device prior to his demise. Maintaining a reserved demeanor and rarely showing strong emotions openly, Nambu demonstrated deep loyalty and a strong sense of justice. He often provided professional justifications for protective actions toward the team to avoid acknowledging emotional attachments. His legacy included unresolved research like a pollution-free energy project and ongoing conflicts with former colleagues such as Dr. Demon, whose betrayal by Galactor led to a tragic confrontation.