Kenji Sahara as Jōji Atsumi
Yumi Shirakawa as Etsuko Shiraishi
Momoko Kōchi as Hiroko Iwamoto
Akihiko Hirata as Ryōichi Shiraishi
Takashi Shimura as Dr. kenjirō Adachi
Susumu Fujita as General Morita
Hisaya Itō as Captain Seki
Yoshio Kosugi as Commander Sugimoto
Fuyuki Murakami as Dr. Nobu Kawanami
Tetsu Nakamura as Dr. Kōda
Yoshio Tsuchiya as Mysterian Leader
The Mysterians, released in Japan as Chikyū Bōeigun (地球防衛軍?, lit. "Earth Defense Force"), is a 1957 Science fiction Tokusatsu film directed by Ishirō Honda and produced & released by Toho Studios. It is notable for being the first Tokusatsu filmed in TohoScope and the first Toho film to use Perspecta stereophonic sound. Allmovie praises the film for its excellent special effects.
The Mysterians (which inspired Rudy Martinez to name his band Question Mark & the Mysterians) was followed by a sequel, Battle in Outer Space. The Mysterians, Battle in Outer Space, and Gorath are considered Toho's space-opera trilogy. For Godzilla vs. SpaceGodzilla (1994), special effects director Koichi Kawakita redesigned the giant robot Mogera into an anti-Godzilla mecha called M.O.G.E.R.A. (Mobile Operation Godzilla Expert Robot Aerotype).
The films starts with Astrophysicist Ryoichi Shiraishi, his fiancee Hiroko, his sister Etsuko, and his friend Joji Atsumi witnessing a festival at a local village near Mount Fuji. Shiraishi then tells Atsumi that he has broken off his engagement with Hiroko but gives no reason other than undisclosed obligation to remain in the village. A mysterious forest fire is then seen near them. Shiraishi rushes out to investigate and disappears during the confusion.
The next day, Atsumi is at the local observatory, where he meets the head astronomer, Tanjiro Adachi. He hands the doctor a report written by Shiraishi. The report concerns a newly discovered asteroid that Shiraishi theorized was once a planet between Mars and Jupiter. He has named it Mysteroid. However, Adachi does not believe in his radical theory and also points out that the report is not complete.
Meanwhile, the village in which Shiraishi was staying is completely wiped out by a massive earthquake. While investigating the area, Atsumi and a group of police officers stumble upon a giant robot, Moguera. The robot then advances on a town near Koyama Bridge that night, and is met by heavy resistance from Japan's self-defense force. However, the conventional artillery has no effect on the war machine, and the automaton continues its rampage until it tries to cross the Koyama Bridge, which is detonated sending the machine crashing down to the ground below destroying it.
At the Diet Building, Atsumi briefs officials on what has been learned about the robot. The remains of the giant machine reveal that it was manufactured out of an unknown chemical compound. Shortly afterwards, astronomers witness activity in outer space around the moon. They alert the world of this discovery, and not long after the aliens emerge, their gigantic dome breaking through the Earth's crust near Mount Fuji.
A group of scientists are politely ushered into the dome, where the Mysterians, a scientifically advanced alien race, list their demands from the people of Earth: a two mile radius strip of land and the right to marry women on Earth. The reason for this is that 100,000 years ago their planet Mysteriod, the once fifth planet from the sun, was destroyed by a nuclear war. Fortunately, some Mysterians were able to escape to Mars before their planet was rendered uninhabitable. However, due to the nuclear war, Stronium-90 has left 80 percent of the aliens population deformed and crippled. The proposed interbreeding with women on Earth would produce healthier offspring and keep their race alive. The latter part of their demands is downplayed as they admit to already taking three women captive and reveal two others that they are interested in, one of which is Etsuko.
Japan quickly dismisses this request and begins the mobilization of its armed forces around Mount Fuji. It's also discovered that the missing Shiraishi has sided with the advance race due to their technological achievements. Japan wastes no time, though, and quickly launches a full scale attack against the Mysterians' dome. However, the modern weaponry is no match for their technology, and Japan's forces are easily fought back.
Distraught by this set back, Japan sends their plea to other nations that they might join together to remove the threat of the Mysterians from Earth. The nations around the world answer the plea, and in no time issue another raid against the Mysterians' dome, this time utilizing the newly developed Alpha and Beta class airships. Sadly, this attack meets failure as well.
The Mysterians then increase their demand, asking for 75 mile radius of land, as the Earth continues to develop a new method of attack. Earth's efforts in this matter pay off as the Markalite FAHP (Flying Atomic Heat Projector), a gigantic lens that can reflect the Mysterians’ weaponry, is designed. Meanwhile, the Mysterians kidnap Etsuko and Hiroko, causing Atsumi to search for, and locate, a back entrance to the Mysterians' dome.
In the meantime, the Markalite FAHP's are deployed by large Markalite GYRO rockets and the final battle against the Mysterians' base of operations commences. As Atsumi, later joined by Shirashi who sacrifices himself in a final attack on the Mysterians after learning of their true ambitions, attacks the base from the inside, the Markalite FAHP's assault the base from above ground. Together, the structure is finally destroyed, the kidnapped women are rescued, and the Mysterians expelled from Earth forever.
The original story of The Mysterians had no monster in it. Mogera's inclusion was a last minute idea as producer Tomoyuki Tanaka felt the film needed a kaiju. Mogera's original concept can still be seen in story board stills, which depicted him as a half mole half reptilian monster. Though the design was never used, some key details were later used in the monster Baragon for the film Frankenstein Conquers the World (1965). Most notably was the monster's burrowing ability, heat ray, and a ridged back. Director Ishiro Honda reworked Moguera into being a robot as a way to further demonstrate the technological power the Mysterians possessed.
The Mysterians Dome was originally to come out of a lake but was changed to coming out of the ground.
The film was released in the U.S. in May 1959. The New York Times called the film "an ear-splitting Japanese-made fantasy, photographed in runny color and dubbed English," and concluded: "This Metro release is crammed with routine footage of death rays and scrambling civilians, not one of whom can act. Tomoyuki Tanaka produced the mess and Inoshiro Honda directed it. Peter Riethof and Carlos Montalban are responsible for the 'English version,' and may it spread no further linguistically."
The original English dubbed version was released at least twice on VHS in the US. Media Blasters released the Japanese version on DVD in 2005 and recorded new English and Spanish audio tracks for the disc. Toho claims it doesn't own the original English dub anymore and thus it was not included on the DVD.
According to MGM records the film made the studio a profit of $58,000.