Ha! Ok, youngster, here's the scoop.... Please remember, I'm getting old, so I may not have it exactly right...
The series never showed them rescued, as I believe they were cancelled after only a few episodes without too much warning, the network having no idea how much of a following they really had - so, no rescue episode.
There was, however, a nostalgic effort to cash in on the cult following many years later (perhaps in the late 70's, or was it the mid-80's). I think it was "Return to Gilligan's Island" or some such title. It was a made-for-TV movie, with all the original cast, except Tina Louise (Ginger), if I recall correctly. In any event, they were all sort of "partners" in a plan to develop the island into a tropical paradise resort. They made some mention of when they were rescued, but no real details, I think. There may have been another TV movie/special, but I don't remember.
I'm sure some of the Freepers out there (or perhaps a Google search) remember better than I, but that's what I can recollect...
Not exactly. They did a show called "Rescue From Gilligans Island" in the late 70's where everyone was picked up and taken off the island. The show chronicled the difficulty they had reintegrating into society, and at the end a plot by a Soviet agent landed them back on the island again.
A couple of years later a second TV movie was made ("Gilligans Island Castaways" if I remember right) in which the people were finally rescued permanently. The Howells ended up buying the island and they all made a fortune after turning it into a resort.
The movies weren't very good, but they did wrap up the storyline. The actual final episode of the series wasn't a finale at all, and was written to be just another random episode. The movies were only made to bring some "closure" to the storyline.
The series ran for three years!
Actually there were 3 TV movies
Rescue From Gilligan's Island
The Castaway's on Gilligan's Island
The Harlem Globetrotters on Gilligan's Island