Harry Truman
David Jackson
Linda Steele
Clyde Whittaker
Otis Kaylor
Sheriff Wayne Temple
Kilpatrick
Hendricks
Mr. Ellison
David Crockett
Lloyd Wagner
Col. Arnholt
Dr. Romarantin
Newscaster
Reeder
Schmitty
Chad
Curry
Bedsoe
Patty Jean
Centers on the events leading up to the cataclysmic 1980 eruption of Mount St. Helens in Washington, with the story beginning on the day volcanic activity started on March 20, 1980, and ending on the day of the eruption, May 18, 1980.