Gigantor (originally Tetsujin 28-go 鉄人28号, literally Iron Man #28) was a manga by Mitsuteru Yokoyama published in 1958 which was later made into several anime series, the first in 1963. It was the first "giant robot" series. It is now being made into a film in Japan based on the old comics as opposed to the newer version in "New Gigantor" which was translated into many languages including Arabic.
There are many indications that Gigantor is a predecessor to another "retro-style" anime, Giant Robo, including the main characters' design/personality similarities.
Cartoon Network's Adult Swim is currently airing the original English version at 5:30 AM (Eastern and Pacific) from Monday/Tuesday overnight to Thursday/Friday overnight, and Saturday/Sunday overnight. It is shown on this block perhaps due to its violent nature for a childrens cartoon, and often "comical" portrayals of villain deaths.
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