An earthquake hits the Hoover Dam, and the people around the area race to safety. While attempting to escape, Kim sacrifices himself to save a young girl.

See the awesome destructive power of landslides.

Landslides can occur without warning. Landslides are events when mountainsides fails and slide down bringing with it mud and debris to engulf the land below. Geologists are studying landslides to find out what causes these catastrophic events without warning.

Strong stormy weather can cause flash floods. This is when heavy rain pours down on a region and very quickly floods an area. Scientists are trying to find ways to warn people before flooding hits by studying weather patterns.

Bill Nye explains what volcanoes are, how they're formed, and what causes an eruption. He then explains the impact of volcanoes on the earth's geography.