The Human Vapor

The Human Vapor, known in Japan as Gas Human No. 1 (ガス人間第一号, Gasu Ningen dai Ichi-gō), is a tokusatsu film produced and released by Toho Studios in 1960. The film was made by Toho's legendary Godzilla directing/special effects/producing team of Ishirō Honda, Eiji Tsuburaya, and Tomoyuki Tanaka.

The film was recut by Brenco Pictures in 1964, changing the format from that of a mystery to a narrative being told largely in flashback from Mizuno's point of view. Even though this version is dubbed, Tsuchiya has stated that he prefers this cut of the film, which he considers to feature his finest performance.

A sequel to this film was planned called Frankenstein vs. the Human Vapor in which the Human Vapor survives the climax and goes to find a doctor who brought Frankenstein's monster to back to life, in hopes of finding a way to bring back his girlfriend who didn't survive the climax leading to a battle between the two. This was dropped in favor of Frankenstein Conquers the World (the 1957 film Tomei-Ningen To Hae-Otoko or Invisible Man vs. Fly Man is available in North America under the title Vapor Man Meets the Human Fly, but it is not related).