From his observation point just five miles from Mount St. Helens, geologist David Johnston said This is it! before his radio went dead. Johnston watched the volcano explode. His body was never found. During the violent eruption on May 18, 1980, the volcano released tons of rock and debris along with scorching steam and poisonous gas. Volcanic ash soared miles into the air, before covering roads and towns. Fifty-seven people died during the eruption, and it forever changed the landscape of the mountain. Author Carmen Bredeson examines the causes and effects of the Mount St. Helens eruption and gives firsthand stories from victims and survivors.