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.
The Amazing Colossal Man is a 1957 American black-and-white science fiction film from American International Pictures. Produced and directed by Bert I. Gordon, it stars Glenn Langan, Cathy Downs, William Hudson, and Larry Thor. It is an uncredited adaptation of Homer Eon Flint's 1928 short science fiction novel The Nth Man. AIP theatrically released it as a double feature with Cat Girl.