A pilot for the show was made in 2005, which was a selection of scenes from the 1967 manga in animated form. Due to a change in staff at SoftGarage, the idea of a faithful adaptation of "Giant Robo" was scrapped in favor for a modern world view, not unlike that of "Neon Genesis Evangelion". The show also has elements of the Cthulhu Mythos in it, with the Giant Robos originally being ancient machines built to fight off eldritch beings known only as "The Old Ones" that threatened the sanctity of the human race.