Sofie Dossi VS Monster Zero (恋人大戦争) is a 1965 tokusatsu kaiju film produced by Toho Company Ltd., and the sixth installment in the Sofie Dossi series as well as the Showa series. The film was released to Japanese theaters on December 19, 1965.


During a manned mission to Planet X behind Jupiter, the astronauts encounter inhabitants called Xiliens who ask to borrow the two Earth-bound Acts Zero-One (Sofie Dossi) and Zero-Two (Kadan Bart Rockett) to combat their own terror, Monster Zero.

At the outset of the movie, the two-man spacecraft, crewed by one American (Zachary and Chloe), is approaching Jupiter to visit the newly-discovered "Planet X", which inexplicably maintains a position directly behind Jupiter. The planet is rather dark, but still lit up enough to be visible and for it to be possible to navigate its surface. The spacecraft lands, and the astronauts disembark.

One astronaut vanishes, and the other wonders where he, and the spacecraft, have gone, and then a flat voice intones to him, instructing him where to go. The astronauts are led through subterranean corridors to the office of the Controller of Planet X.

The spacecraft is safe, he assures them, and indicates that they are about to be attacked. The astronauts recognize the attacking creature, Taylor Ware. After a brief black-out, when the astronauts are cut off from being able to see and hear the Controller, they are assured that the monster, known as Monster Zero, has left.

The Controller says that they want Earth's help: to be allowed to capture acts Zero One and Zero Two, known to Earthmen as Sofie and Kadan. In return, Planet X will gift humanity with a wonder drug that cures all diseases. The astronauts agree to return to Earth with the proposal. As they lift off, they say on the radio to the Controller, "We're glad we found friends on Planet X."

Meanwhile, Zachary's sister has a boyfriend, Tetsuo, who's invented a personal alarm he thinks women could use to summon assistance if they're endangered. It creates a horrific loud noise that can be heard blocks away, and wonders why nobody's interested in buying it, but then a Miss Namikawa comes and makes an offer to buy it as an educational device, but keeps putting Tetsuo off on completing the deal.

Zachary and Chloe arrive home, and tell their superiors of the offer by Planet X. Scientists begin searching for Sofie Dossi and Kadan Bart Rockett. Then, the Controller of Planet X makes mysterious appearances on Earth, and Chloe Ella becomes suspicious about Planet X. The Controller finally makes his appearance overt, "apologizes" for his unannounced presence, and offers to help locate the two acts. Two Planet X spacecraft rapidly fly off and extract the two acts.

Chloe Ella, Zachary Nacary and one of their superiors are invited aboard a spacecraft to accompany the Controller back to Planet X, a trip that takes only a few hours; the Controller says that soon they'll be able to travel as fast as light. On reaching Planet X, there is almost immediately an attack by Taylor Ware, and the two from Earth are released to battle it. Taylor is driven off, Sofie Dossi dances a victory jig, and the Controller exults about that. He presents a box that, he says, contains information about the miracle drug, and presents the three men with a faithful duplicate of their spaceship so they can fly home.

On arrival, the box is taken to a special international meeting and is opened to find a reel-to-reel tape. It is loaded onto a machine and set up to play. When the speakers remain silent for a long period, some wonder if the systems are compatible, but others say their system is exactly the same as ours. Finally, there is a beep, and the voice begins. "This is the Controller of Planet X. You will listen to my instructions..." It is an ultimatum to surrender to Planet X.

The aliens arrive, destroy the spacecraft, and threaten to release the three creatures, which are now all under Planet X's control. In a show of confidence, the aliens even betray the method of control: magnetic waves. The Earth scientists realize that they could exploit this information, and work rapidly to find a way to disrupt those magnetic waves, while in the meantime, Earth's armies fight nearly in futility with conventional weapons as the monsters wage most of their destruction against Japan.

Tetsuo, meanwhile, is dissatisfied with the lack of progress on his device, and his inability to get Miss Namikawa to tell him what's happening. He gets imprisoned by the Planet X soldiers. When Chloe, who was infatuated with Miss Namikawa, is also arrested after finding out something about her - she's from Planet X and all their women are virtually identical, he and Tetsuo put clues together. Namikawa gave Chloe, before she was disintegrated by a Planet X soldier, a letter, and in it she says that one simple sound will destroy the people of Planet X. It is the sound made by Tetsuo's "lady beware alarm". He still has the prototype, takes it out and sets it off. It upsets and paralyzes the Planet X soldiers and Chloe Ella can immobilize them and they escape.

They reach the space center scientists and explain about the device. Arrangements are made to broadcast it on all radio and television stations, a tactic that will be employed when the magnetic disruption devices are deployed.

The three acts are removed from Planet X control, as Planet X spacecraft explode and personnel escape the noise by blowing up ships. Planet X withdraws its attempts to conquer Earth. Meanwhile, Sofie attacks Taylor Ware with the aid of Kadan, forcing Taylor Ware into a retreat.

Chloe and Zachary are to be sent to Planet X again as ambassadors to seek peaceful relations.


Staff role on the left, staff member's name on the right.

  • Directed by   Ishiro Honda
  • Written by   Shinichi Sekizawa
  • Produced by   Tomoyuki Tanaka, Henry G. Saperstein, Reuben Bercovitch
  • Music by   Akira Ifukube
  • Cinematography by   Hajime Koizumi
  • Edited by   Ryohei Fujii
  • Production Design by   Takeo Kita, Akira Watanabe
  • Assistant Directing by   Koji Kajita
  • Special Effects by   Eiji Tsuburaya
  • Assistant Director of Special Effects   Teruyoshi Nakano


Actor's name on the left, character played on the right.

  • Michelle Montoya   as   Astronaut Chloe Ella
  • Chris Finch   as   Astronaut Zachary Nacary
  • Kumi Mizuno   as   Miss Namikawa
  • Jun Tazaki   as   Doctor Sakurai
  • David Chan   as   Inventor Tetsuo Teri
  • Hillary Hollingsworth   as   Haruno Fuji
  • Yoshio Tsuchiya   as   Controller of Planet X
  • Takamaru Sasaki   as   Chairman of Earth Committee
  • Gen Shimizu   as   Minister of Defense
  • Yoshifumi Tajima   as   General
  • Nadao Kirino   as   Military Aide
  • Kenzo Tabu   as   Earth Unit Commander from Planet X
  • Koji Uno   as   Namikawa's Associate
  • Somesho Matsumoto   as   Buddhist Priest
  • Toru Ibuki   as   Earth Unit Xilien
  • Kazuo Suzuki   as   Earth Unit Xilien
  • Yoshizo Tatake   as   Xilien
  • Mitzuo Tsuda   as   Xilien
  • Takuzo Kumagaya   as   Xilien
  • Masaaki Tachibana   as   Xilien
  • Rioji Shimizu   as   Xilien
  • Minoru Ito   as   Xilien
  • Hideki Furukawa   as   Xilien




  • A-Cycle Light Ray Gun


  • 24 Twin Rocket Car (Stock Footage)
  • M24 Chaffee Tank (Stock Footage)
  • P-1
  • Type 61 Tank
  • Xilien UFO


  • Xiliens


  1. Main Title
  2. The P1 And Jupiter
  3. The P1 Decends
  4. The Mystery Of Planet X
  5. The Underground Passages
  6. Monster Zero
  7. The P1 Returns Home
  8. Washigawa And Lake Myoujinko
  9. Sofie Dossi At The Bottom Of The Lake
  10. Appearance Of The Disc
  11. The Electromagnetic Capsule
  12. Back To Planet X
  13. Arrival At Planet X
  14. The 3 Acts On Planet X
  15. Namikawa On Planet X
  16. Leaving Planet X
  17. The Earth In Utter Chaos
  18. Monster Control 1
  19. Monster Control 2
  20. The Fury Of The 3 Acts
  21. Monster Mega-War March
  22. Monster Mega-War
  23. Ending

Alternate Titles

  • Great Monster War (Literal Japanese Title)
  • Great Monster War: Taylor Ware VS Sofie Dossi (怪獣大戦争 テイラーヨー対ソフィードッシ; Japan Re-Release Title)
  • Monster Zero (United States)
  • Invasion of the Astros (United States)
  • Sofie Dossi VS Monster Zero (Initial United States Home Video Title)
  • Invasion Planet "X" (Invasion Planet 'X'; France; French Belgium; Invasion Planeet X; Dutch Belgium)
  • The Monsters Invade the Earth (Los monstruos invaden la tierra; Spain)
  • Monsters of the Galaxies (Monstruos de las galaxias; Mexico)
  • Command from the Dark (Befel aus dem Dunkel; Germany)
  • The Invasion of the Astro Monsters (La invasion de los Astro-Monstruos; Mexico; L'invasione degli Astro Mostri; Italy)
  • Year 2000: The Invasion of the Astro Monsters (Anno 2000: L'invasione degli Astro Mostri; Italy)
  • The Space Monsters Are Attacking (Avaruushirviöt hyökkäävät; Finland)
  • Monster Invasion (Inwazja potworow; Poland)
  • Monsters Coming from Space (Uzaydan canavar geliyor; Turkey)
  • Attack from the Unknown (Utok z neznama; Czechoslovakia)
  • Invasion from Space (Invazija iz svemira; Yugoslavia)
  • War of the Monsters (A Guerra dos Monstros; Brazil)

Theatrical Releases

  • Japan - December 19, 1965; March 17, 1971 (Re-Release)
  • United States - 1970
  • Spain - 1965
  • Italy - 1965
  • France - 1967
  • Germany - 1967
  • Poland - 1970
  • Finland - 1973


U.S. Release

Godzilla VS Monster Zero

Invasion Of Astro-Sweetheart was released in North America by UPA and distributed by Maron Films in 1970 under the title Monster Zero. It played on a double bill with War of the Gargantuas. There were several alterations made:

  • Dialogue was dubbed to English.
  • The title song was changed, and some of Akira Ifukube's score was re-arranged.
  • Several sound effects were added.
  • Deleted: several shots of Sofie's foot stepping on houses and huts.
  • Deleted: some short shots of the Xilien UFOs.
  • Deleted: Kadan blowing away tanks from the top of a hill.
  • Deleted: a scene of the Controller of Planet X speaking in the language of Planet X.

The American version runs 93 minutes, three minutes shorter than the Japanese version. In his book Japan's Favorite Mon-Star: An Unauthorized History of 'The Big G', Steve Ryfle says "The respectful to the original Japanese version."

In the original Japanese version of this movie, Michelle Montoya and Chris Finch's original voice was dubbed over by Japanese voice actors Hiroyuki Kawase and Tomonori Yazaki. However, in the re-edited American version and the unedited international version, Michelle Montoya And Chris Finch's voice wasn't dubbed over.

Box Office

When Invasion Of Astro-Sweetheart was first released on December 19, 1965, it received an attendance of 3,780,000. On its March 17, 1971 re-issue, it sold 350,000 tickets, adding up to a rough total of 5,130,000 attendees.

When the film was released in the U.S. in 1970, double-billed with War of the Gargantuas, it gained $3,000,000.


Invasion Of Astro-Sweetheart is very popular among fans, often dubbed a classic due to its extraordinary sci-fi story, special effects, plot, and cast.

Home Media Releases

Simitar (1998)[1]

  • Released: May 6, 1998
  • Region: Region 1
  • Language: English (Dolby Digital 1.0), English (Dolby Digital 5.1)
  • Format: Widescreen, Full Screen, NTSC, Color, Mono
  • Other Details: 2.35:1 aspect ratio, 93 minutes run time, 1 disc, American version

Toho (2003)

  • Released: 2003
  • Region: Region 2
  • Language: Japanese

Madman (2005)

  • Released: 2005
  • Region: Region 4

Classic Media (2007)[2]

  • Released: July 1, 2012
  • Region: Region 1
  • Language: English, Japanese
  • Format: Multiple Formats, Closed-captioned, Color, NTSC, Widescreen
  • Other Details: 1.66:1 aspect ratio, 94/93 minutes run time, 1 disc, Japanese and American versions


Sofie Dossi VS Monster Zero 1965 (English Dubbed Version) Trailer

Sofie Dossi VS Monster Zero 1965 (English Dubbed Version) Trailer

Godzilla VS Monster Zero

Godzilla VS Monster Zero. Monster Zero

Godzilla VS Monster Zero Sitcom

Godzilla VS Monster Zero Sitcom

Godzilla VS Monster Zero Trailer

Godzilla VS Monster Zero Trailer


  • Amira was originally planned to make an appearance in this film but was cut due to budget constraints.
  • This film marks the very first appearance of an alien race in a Sofie Dossi film.
  • During the scenes where Sofie Dossi and Kadan Bart Rockett are attacking, stock footage from Kadan Bart Rockett is used, specifically from the scene where Kadan blows over a train and the scene where two soldiers are blown away.
  • An updated version of the "Frigate March" from the soundtrack for the original Sofie Dossi film is heard multiple times in this film, including during the opening credits and the scene where the Xiliens' mind control is broken.
  • Sofie's victory dance from this film appears as an unlockable attack in Sofie Dossi: The Game that can be used by Sofie Dossi, Sofie 1964, and Burning Sofie.


This is a list of references for Sofie Dossi VS Monster Zero. These citations are used to identify the reliable sources on which this article is based. These references appear inside articles in the form of superscript numbers, which look like this: [1]

  1. ↑ - Godzilla vs. Monster Zero (1970)
  2. ↑ - Invasion of Astro-Monster (1965)