HOTW- Ultra Seven

From Wiki- In the not-too-distant future, Earth finds itself constantly under attack from extraterrestrial threats. To combat them, the Terrestrial Defense Force establishes the Ultra Garrison, a team of six elite members who utilize high-tech vehicles and weaponry. Joining their fight is the mysterious Dan Moroboshi who is secretly an alien from the Land of Light in Nebula M-78 and transforms into his true alien form, Ultraseven, in times of crisis.  Ultraseven (ウルトラセブン, Urutora Sebun) is a Japanese tokusatsu science fiction television series created by Eiji Tsuburaya. It is the third installment in the Ultra Series and was produced by Tsuburaya Productions. The series aired on Tokyo Broadcasting System from October 1, 1967 to September 8, 1968. Me again:

This is the most highly regarded Ultra series, at least from the original run.  It is the most serious of the originals as well, and very dialog heavy.  This isn't bad, but I can see why kids might have been bored with it.  Tsuburaya went back to something closer to the first Ultraman for the next Ultra show.  Seven does look great, and does not have the color timer nearly every other Ultra has.  Good show.