The righteous heroine Silver Extra who flew in from outer space usually protects the peace of the earth as the only female member of the Earth Garrison. However, Extra, who rescued the doctor in the nick of time, hears from the doctor that the Weimar aliens are trying to invade the Earth by scattering the seeds of alien man-eating plants. Extra rushes over, but the man-eating plant grows at an abnormal speed and swallows the doctor. The extras absorbed into the body of the man-eating plant are attacked by parasites that live inside the monster. Can the extras escape from the monster's body?