By 1971, tokusatsu was firmly entrenched as a genre. The consistent success of Ultraman led to competitors and imitators. Shotaro Ishinomori's Kamen Rider, which debuted in April of 1971, was about a masked, motorcycle riding crusader of justice with a grasshopper themed costume, and would spawn its own massive franchise as a result. However, Kamen Rider is regular sized, and it will be a while before one of those series gets the spotlight on Shin Super Robot Sunday.
In December of 1971, Tsuburaya Productions would debut a spinoff of Ultraman, which was based off a manga from 1969. More serious in tone than (most) of the Ultra series, Mirrorman, told the story of Kyôtarô Kagami, a photojournalist who learns he's the half-human son of a fallen hero from the 2nd Dimension: Mirrorman. Set in the 1980s, this new Mirrorman must grapple with his destiny as Earth's only hope against a hostile alien race known as The Invaders.
Mirrorman takes place in its own self-contained universe, and wasn't part of the Ultra franchise per se. Armed with powers similar to Ultraman's, but with the ability to reflect attacks, travel through mirrors, and other light and mirror themed abilities. He doesn't fly, but he can run at the speed of light. Fighting alongside the Science Guard, the first half of the series focuses more on investigations and serious storytelling.
Much like Mighty Jack, the ratings began slipping, partly due to a boom in other superhero shows like Silver Mask, which was a direct competitor for viewers. The course of the show was changed to a more traditional tokusatsu show with fewer recurring monsters, stronger themes of good vs. evil, and Mirrorman himself got an equivalent of an Ultraman's color timer; meaning he had an operational time of three minutes before a bomb implanted in his superhero body would explode.
Alongside an array of giant monsters that challenged Mirrorman, there was also the robot kaiju, Noah. A female robot disguised as a human to infiltrate and brainwash a marching band into being agents of the Invaders. Naturally, she can transform into a giant robotic beast form standing 45 meters (146 ft) tall that can shoot missiles and energy beams.
Mirrorman would run for a very respectable total of 51 episodes, but it didn't catch on like Ultraman, and the character wouldn't be revisited until 2005, with a three episode direct-to-video miniseries called Mirrorman REFLEX (which was later edited into a movie). This series had a brand new Mirrorman with a design closer to the manga's and a darker tone similar to the first half of the show's. The series taps into Japanese mythology, so no giant robots, but it was worth mentioning because he looks damn cool.
Mirrorman would get revisited yet again, but we'll get to that when we get to that.
Next time on Shin Super Robot Sunday: Tsuburaya plays an Ace.
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