|“||Godzilla and Biollante aren't monsters. It's the unscrupulous scientists who created them who are the real monsters.||„|
— Dr. Genshiro Shiragami, Godzilla vs. Biollante
After the raid of Godzilla in 1984, a group of Japanese soldiers scours the ruins of Tokyo in search of left behind Godzilla cells. Suddenly, the soldiers are assaulted by agents of Bio-Major, an American scientific corporation, who steal the cells. Before the agents can escape with the cells, an assassin from Saradia called SSS9 kills them and takes the samples back to Saradia. There, Dr. Shiragami is working for the Saradia Institute of Biotechnology in order to genetically engineer plants to grow in the arid deserts of the nation. This, the government hopes, will gradually take the country away from relying only on oil exports for profit, and will hopefully make them the world's largest grain exporter, threatening the status of more powerful nations like the United States and Japan. Using the imported Godzilla cells, Shiragami and his botanist daughter Erika hope to breed these immortal plants. However, before this can become a reality, Bio-Major bombs the laboratory, killing Erika in the process and destroying most of Shiragami's experiments. Grief-stricken, Shiragami returns to Japan, unwilling to continue his experiments. A few years later, in 1989, Shiragami tried to keep his daughter alive by splicing what little DNA he could retrieve from her into a rosebush. He also enlisted the help of psychic Miki Saegusa to check for psychic waves coming from the rosebushes. Little did he know that both Bio-Major and SSS9 were watching from afar. When an earthquake destroys the rosebush, Shiragami agrees to take part in a bio-weapon project with the Japanese government so that he can have access to a supply of Godzilla cells and use them to keep the roses alive. After Shiragami successfully splices Godzilla cells into one lone rose, it begins to rapidly mutate into the monster Biollante. Two Bio-Major agents, John Lee and Michael Low, raid Shiragami's laboratory to find his notes on the bio-weapon project, the Anti-Nuclear Energy Bacteria. There, they are attacked by SSS9, but the battle is interrupted when Biollante attacks all of them, killing Low and forcing the others to retreat. Biollante then leaves the lab and takes root in the nearby Lake Ashi, taking the form of a gigantic rose. Godzilla, freed from Mt. Mihara by a Bio-Major bomb, eventually arrives at the lake, and battles Biollante, seemingly killing her, much to Shiragami's dismay. However, Biollante breaks apart into spores of energy and floats away, causing Shiragami to realize she is immortal and cannot die after all. Later at the Wakasa plain, Shiragami witnesses the final battle between Godzilla and Biollante in her second form, and becomes grief-stricken when Biollante has to leave Earth after being mortally wounded. Eventually, he accepts that Biollante and therefore Erika is still alive in the form of spores after seeing Erika's face as Biollante floats into space, but he is immediately shot and killed SSS9, who is later killed by Sho Kuroki when standing on a M6000 T.C. System pad.
Video Game Appearances
Doctor Shiragami later reappears in Godzilla: Unleashed as a member of the human council. He accidentally creates Biollante under General Gyozen's instructions to create an anti-monster mutagen. He also makes a breakthrough in understanding what the Power-Surge crystals do to the kaiju. In the PS2 version, due to the absence of Biollante, his role is deeply reduced.
- Doctor Shiragami is among the first human characters to create a kaiju, but did not have malicious intentions in doing so, only seeking to preserve his daughter's soul.
- In Godzilla: Unleashed, Shiragami's overall appearance is radically different to his film counterpart. He resembles a stereotypical American scientist with a flowing white labcoat and thick-rimmed glasses.