Godzilla vs. Biollante
Saegusa made her debut in "Godzilla vs. Biollante". As well as being an instructor of an institution for psychic children, she also served as an assistant to Doctor Shiragami, a botanist studying the psychic energy of roses. Unbeknownst to Saegusa, Shiragami combines the DNA of one of his roses with genetic material taken from his late daughter Erika and the mutant dinosaur Godzilla. The resulting monster, named Biollante, escapes from the laboratory and takes residence in Lake Ashino. For the duration of the creature's passivity, Saegusa sensed that it was in fact possessed by Erika's spirit. After Godzilla defeats Biollante for the first time, he heads toward a nuclear power plant, intent on absorbing its energy. Saegusa confronts Godzilla and nearly puts herself into a coma by bending Godzilla's will into leaving the area.