Continuity mistake: The professor mentions he can't drink vodka with the Russians because he's allergic to alcohol, yet in the episode "Man with a Net" (with Lord Beesley), he drinks a strong alchoholic drink he made along with everyone else with no signs of any sickness, or reaction preventing him from drinking it.
Gilligan's Island (1964)
1 continuity mistake in Nyet, Nyet, Not Yet
Starring: Alan Hale Jr., Jim Backus, Bob Denver, Natalie Schafer
Revealing mistake: Near the end of the episode, all the castaways are passed out cold when Lord Beasley finally catches his butterfly. Right after saying the line "That's the trouble with you Americans - you simply don't know how to hold your tea" as he's exiting off camera, Mrs. Howell starts to open her eyes slightly, but then quickly shuts them again. Perhaps she thought the cameras stopped rolling.
Skipper Jonas Grumby: Ginger, I've got a problem... I've got a real problem... Now you're a girl, right?
Ginger Grant: Well, if you're not sure about that, you have got a problem.
Trivia: In the opening credits of the black-and-white episodes, the US flag at the marina is at half-mast because the opening was filmed shortly after the Kennedy assassination.
Question: Why did the Howells, Ginger and Mary Ann have so many changes of clothes with them? It was only a three hour tour.
Answer: I've been binge watching it, and a couple of times trunks with costumes have washed ashore, and in one episode the professor figured out how to make thread for weaving cloth.
Answer: Bob Denver answered this when he was on a talk show hosted by Pat Sajak. He said they were going to write into an episode where the castaways found all these clothes, but it got too complicated, so he said, they decided, "who cares, it's only a TV show," and forgot about it. So the writers and actors even asked this, they just never bothered to address it.