Who Mourns for Adonais? - S2-E2
Trivia: An ending that was planned but abandoned for this episode would have revealed that Lieutenant Palamas was pregnant with Apollo's child.
Trivia: The episode "Patterns of Force" was aired only once on German TV, after which it was prohibited to be broadcast by any German TV station again to this day, because of its Nazi theme.
The Trouble With Tribbles - S2-E15
Trivia: Prop master Jim Rugg "animated" the tribbles by inserting wind-up toys under their fur to make them crawl, and by supplying some with small balloons and concealed air hoses, making them appear to breathe.
Trivia: Paramount's press releases in 1967 claimed that the Soviet news agency Pravda had complained about Star Trek having no Russian characters, so they were adding Chekov. This story was completely bogus. (Star Trek never aired in the U.S.S.R.) NBC wanted to appeal to the 8-14 teenybopper crowd, and asked Roddenberry to add a character who looked like Davy Jones of the Monkees. So Chekov debuted in season 2, replete with a bad Beatle wig that was, thankfully, soon jettisoned.
Trivia: This episode was originally intended to be a pilot episode for a spin-off show for the character Gary Seven. This is why Robert Lansing's name appears at the start of the show.
The Trouble With Tribbles - S2-E15
Trivia: One week after shooting, William Campbell (the Klingon captain) returned to the set and collected some of the Tribbles for children in his neighbourhood. But when the episode was eventually aired, he was swamped by requests for Tribbles.
Trivia: At the very end, in talking about the future of the two characters, Spock says, "We could say that Mr. Seven and Miss Lincoln have some interesting experiences in store for them." While this seems like a strange thing for him to say, this episode was a "backdoor pilot" for a spinoff series with the same title (see Teri Garr's Wikipedia entry). But the idea wasn't sold and Mr. Seven and Miss Lincoln never had any further interesting experiences. The Enterprise's history log was evidently wrong.
Trivia: Some parts of the film Kirk and Spock watch are historical footage, some of it is made specially for this episode. If you look very closely you can see the Fuhrer Adolf Hitler in a car at one of his ceremonies. Beware he is hard to spot, because most of the time his head is behind some flags. (00:06:20)
The Trouble With Tribbles - S2-E15
Trivia: The intention of introducing the Klingon Capt. Koloth was to bring in a counterpart and recurring adversary for Kirk, but that intention was never carried out.
Trivia: The title "Return to Tomorrow" didn't translate well into other languages. So in France, the episode became "You Are Nothing But Dust"; in Japan, "Energy at 160 Kilometers Underground," and in Germany, "Ghost Craves Body!"
Trivia: The front of the Ekosian Chancellery is an actual office building of Paramount Pictures.
Who Mourns for Adonais? - S2-E2
Trivia: The hand seen stopping and holding the Enterprise is Gene Roddenberry's.
The Trouble With Tribbles - S2-E15
Trivia: According to the screenwriter David Gerrold, the producers of the show noticed a similarity of the plot line and story concept to Robert A. Heinlein's story "The Rolling Stones" and asked Heinlein for permission to use the idea. Heinlein asked for an autographed copy of the script, but otherwise did not object, noting that both stories owed something to the Ellis Parker Butler's 1905 short story "Pigs is Pigs" and perhaps "Noah". (Source "The Trouble With Tribbles: the birth, sale and final production of one episode" by David Gerrold).
Trivia: Director Marc Daniels employed an old trick to save Nona's topless bathing scene from NBC's censors. He deliberately shot twice the needed footage, including risque side shots exposing portions of bare breast. After the censors excised the "most naked" portions, what remained was precisely what Daniels had wanted to begin with: a bare-backed Nona bathing in the waterfall.
The Trouble With Tribbles - S2-E15
Trivia: Stanley Adams, who appears in this episode as Cyrano Jones the tribble peddler, later co-wrote the season 3 episode "The Mark of Gideon".
Answer: Kirk was getting his physical and Dr. McCoy probably turned off communications, because if he hadn't, Kirk would have left and headed straight for the bridge, leaving McCoy irritated.