[Machine Translation] The first in the Showa era's imaginative special effects series! The Invisible Man and the Fly Man, two popular monsters, face off in this film directed by Mitsuo Murayama and featuring special effects by Toru Matoba. A man discovers a chemical that turns humans into the same size as flies, and begins to take revenge on the people who framed him for war crimes. Physicist Tsukioka decides to become invisible to save people from the fly man's terror.