Phantoma Phantaman: Warrior of Justice (lost English dub of "Ōgon Bat" anime series; 1967)
Ōgon Bat (黄金バット literally "Golden Bat") is a Japanese superhero series created in 1930, featuring the eponimous hero and his fight against Dr. Erich Nazo, the main antagonist of the series.
Originally a Kamishibai (traveling local shows consisting on telling stories while scrolling illustrated prints), the series was eventually adapted into a manga, an anime series and eventually transformed into a feature movie distributed by Toei Japan.
It's notable for being one of the very first Japanese superheroes and for pre-dating both American comic book characters Superman and Batman (created in 1938 and 1939, respectively).
In 1967, an anime adaptation of Ōgon Bat was produced by Yomiuri TV, based directly on the manga adaptation. During the same year, the series was picked up by Nine Network in order to be localized for western audiences under the name Phantoma Phantaman: Warrior of Justice.
The series was originally scheduled to be aired for both American and Australian audiences but for unknown reasons, the series was never released on American territories, Australia being the only country where the English localization was ever broadcast.
For a long time, the English localization was believed to never have been produced, as no footage ever surfaced, until a clip (albeit poorly recorded) was uploaded in 2012 to YouTube, posted by user TVNostalgia, showing that in fact an English localization was made.
It is unknown why the show never aired in the U.S., but now that the existence of the clip was made public, there is hope that more footage will resurface eventually on the net. However, due to the age of the show itself, it's unlikely that more episodes will ever see the light of day as the possibility of them being recorded during the 1960's is very low.
The English dub never received a VHS or DVD release, even in Australia.
It's worthy to note that the series was actually translated in Spanish as "Fantasmagorico", with surviving episodes and official VHS releases found around the Internet.