In its native Japan, the film was released to theaters as a mini-serial, with two hour-long episodes. In the US, it was edited into a single feature film running less than 90 minutes.
If Krankor is around 500,000 miles from Earth, it would be the closest planet to Earth in our solar system. It would be twice as far from Earth as the moon, and tens of millions of miles closer than Venus or Mars.
Was shown on an episode of Mystery Science Theater 3000, Season 9 Episode 16
This film is very loosely based on a TV series of the same title ("Yûsei Ôji"/"Planet Prince") from the previous year, produced by the company Senkosha, and running at 48 episodes (divided into 4 serials). The version of the titular hero as seen in the series looks more similar to Shintoho's Super-Giant/Starman (a cape and cowl, only his face is not covered). Toei's 2-part movie version features a radically different design from the Senkosha TV series, wearing a streamlined caped costume and an elaborately designed helmet with a mask covering the top half of his face. He is mostly invulnerable, compared to his Senkosha TV counterpart, who, while a great fighter, also often gets into long, painful perils.
This was originally shot in the Toeiscope anamorphic widescreen process (2.35:1). For the U.S. television release by Walter Manley Enterprises, the image was truncated to the standard academy (1.33:1) format but selected special effects shots were letterboxed with a white border on the top and bottom of the screen.