The answer to that question is no, but Gary Seven has appeared in a number of non-canon works[1], including the Year Five IDW comics series from as recently as 2020.
Been a good while since I did one of these - when a 'current' series is running, I will focus on that. In any event, Discovery is on hiatus until February, so I might do a couple more of these before then.
****
In a spot of rather casual time travel, the Enterprise goes back to 1968 to observe Earth's history and find out how the planet dealt with historical problems back then. As they're doing so, they intercept a transporter beam from a thousand light years away, with a suited man and his black cat. Who it turns out has advanced alien technology and plans to do something on Earth. Can the crew stop him? Should they stop him?
****
Star Trek was not doing well in the ratings during its second run and Roddenberry basically created the episode I am reviewing as a "backdoor pilot" for another show that was ultimately not picked up. NBC, convinced by among other things a mass letter writing campaign, renewed Star Trek, but... more on that in another post.
The plot is very Cold War in its basis and would have worked just fine as a standalone episode. A mysterious operative with high-tech gadgets (including an early version of a speech-to-text machine, a concept under development, but still very primitive at the time) that could be mucking around in Earth's history... definitely a good idea. Space nukes were something in the headlines at the time - the Outer Space Treaty banning them had been signed and ratified in 1967.
The execution, however, is rather lacking. The Enterprise regulars are fine. Zero complaints about any of them - Sulu turns up as well in this one.
But then you've got those for the proposed spin-off series, Gary Seven and Roberta Lincoln. Gary Seven is a rather forgettable character, one of those generic action heroes that fill so much of television even today. Any series would have likely built on his background of course. As for Roberta Lincoln, the very-of-her-time secretary, she's a 'dumb blonde' who in one case literally advances the plot with her backside. As for Isis the cat, who is very well trained (any cat owner can tell you that getting one to do what you want is not easy), the revelation at the end really cheapens the character. Terri Garr would go on from this to get much better roles, including an Oscar nomination.
The rest of the guest cast... not really memorable... and look more than a bit silly after being hypnotised by Gary Seven. I wonder when the NYPD got rid of the double-breasted overcoats? They certainly don't wear them now. Feel free to respond in the comments.
There is a lot of stock footage of a Saturn V in this story, which would of course be the rocket that took man to the Moon for the first time, although it had only made one test flight at this point. It does seem a very odd choice for the space nukes described in the episode - there were plenty of far less powerful rockets in the US inventory that could do the job just fine. This footage in any event provides a considerable amount of padding.
That's the problem with this episode. It's too slow and padded out with not very good set-up for a series. The denouement is great as Spock and Kirk have to work out if they can trust Gary Seven... but that's the best part of the episode.
Ironically and tragically in the latter case, shortly after this episode aired, a Saturn V did have problems[2] and there was an "important assassination" - namely Martin Luther King Jr., who had persuaded Nichelle Nichols to stay on the show as she was an inspiration to young black women.
****
Conclusion
The concept is interesting, but let's be honest, I would not be joining the Gary Seven Army.
Oh, and "Spock's Brain" is next... I will brace myself.
6/10
[1]CBS policy is basically that only the TV series and films are 'canon'. The Abrams films from 2009 onwards are considered part of an alternate reality called "the Kelvin timeline" after the ship that was attacked at the beginning of the first of those, a term that has become official. The Animated Series went from being canon to non-canon to de facto canon again. In any event, stuff from these works has turned up in TV and film, therefore becoming canon, such as James Kirk having the middle name Tiberius.
[2]Apollo 6 had been planned to simulate a lunar return profile and had a number of engine problems meaning that the full mission plan could be achieved. In any event, with Lyndon Johnson's decision not to seek re-election and MLK's assassination, followed by mass riots, meant that the thing was rather ignored in the press.