7-Color Mask (七色仮面 Nana-Iro Kamen) is the name and title character of a tokusatsu TV series, later called New 7-Color Mask (新七色仮面 Shin Nana-Iro Kamen).
Created by Kōhan Kawauchi (who also created Moonlight Mask), this B&W TV show was the first-ever superhero TV series by Toei Company Ltd.. It was broadcast on NET (now TV Asahi) from June 3, 1959 to June 30, 1960, with a total of 57 episodes (divided into 7 segments).
Aside from being Toei's first superhero show, this series was also the debut of actor Sonny Chiba (who was 19 at the time), who took over the title role from Susumu Wajima after Episode 32.
The hero of this series is a young detective named Kotarō Ran, who, unknown to anyone (even his friends), is a master of disguise, utilizing 7 different personalities. Most of his disguises are odd characters, like a magician and a cigar-smoking Indian, but Kotarō's 7th disguise is the 2-gun-toting caped, golden-masked superhero - 7-Color Mask!
This series was "remade" by creator Kawauchi in 1972 as Warrior of Love, Rainbowman, and it is also considered an inspiration behind Go Nagai's Cutey Honey.