Coniston Water per hour () in "Blue Bird K4". Between 1956 and 1959 Sir Malcolm's son Donald Campbell set four successive records on the lake in "Bluebird K7", a hydroplane. In 1966 Donald Campbell decided that he needed to exceed 300 miles per hour (483 km/h) in order to retain the record. On 4 January 1967, he achieved a top speed of over 320 miles per hour () in "Bluebird K7" on the return leg of a record-breaking attempt. He then lost control of "Bluebird", which somersaulted and crashed, sinking rapidly. Campbell was killed instantly on impact when decapitated by the K7's
The H-Man rescue team discovers them both, with the H-Men in hot pursuit. The water is then ignited, burning alive all of the monsters and putting an end to their reign of terror. The narrator delivers a final statement, that with the continuing H-bomb tests, the next ruler of the Earth may be the H-Men. The original Japanese version of the film focuses a similar amount of time on the drug-running criminals as the activities of the "H-Men". This was cut in the American film. "The H-Man" was distributed theatrically in Japan by Toho on June 24, 1958. The film was released