Lt. Col. Glenn Manning is inadvertently exposed to a plutonium bomb blast and although he sustains burns over 90% of his body, he survives. Then he begins to grow, but as he grows he starts losing his mind. By the time he stops he is 50 ft tall, insane and is on the rampage.

Glenn Langan
as Lt. Col. Glenn Manning

Cathy Downs
as Carol Forrest

William Hudson
as Dr. Paul Linstrom

Larry Thor
as Maj. Eric Coulter, MD

James Seay
as Col. Hallock

Russ Bender
as Richard Kingman

Hank Patterson
as Henry

Frank Jenks
as Truck Driver

Jimmy Cross
as Sergeant at Reception Desk

June Jocelyn
as Nurse Wilson