Starring: Alan Hale Jr., Jim Backus, Bob Denver, Natalie Schafer
St. Gilligan and the Dragon - S1-E21
Revealing mistake: When the ladies are cleaning up their hut, Mrs. Howell mentions that she'd broken several nails that day. While Ginger mentions that she broke eleven—one nail twice. When you look in closely at her sides, her manicure is still very much intact.
Professor Roy Hinkley: Well, that glue is permanent! There's nothing on the island to dissolve it. Why do you know what it would take? It would take a polyester derivative of an organic hydroxide molecule.
Thurston Howell III: Watch your language! You're in the presence of a lady.
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.