Ultraseven: S1 E20 - Destroy Earthquake Epicenter X Ultraseven

Dan and Soga visited Professor Iwamura, who is known as a stubborn old man, at International Nuclear Research Center, to request for corporation for the frequent earthquakes hitting the Aosawa mountainous area, but got turned away at the door. Shortly after, Ultra Guard met a college girl who was engaged in a mountain rally and finds out she carried substance called "Ultonium", a nuclear that form Earth. This stunned Dr. Iwamura and he started to fear that Earth may collapse.