The Amazing Colossal Man

After being accidentally exposed to a plutonium bomb blast, Lt. Col. Glenn Manning survives but begins to grow at an alarming rate. As his body expands to a colossal size, his mind deteriorates due to an inadequate blood supply to his brain. Now a 60 foot giant driven by insanity, he escapes captivity and terrorizes the city of Las Vegas, leading to a dramatic confrontation at the Hoover Dam.