Gilligan's Planet was a Saturday morning cartoon produced by the Filmation animation studio which aired during the 1982-1983 season on CBS. It was the second animated spin-off of the classic television program Gilligan's Island (the first being 1974's The New Adventures of Gilligan), as well as the last cartoon that Filmation produced for Saturday mornings; afterwards, they produced cartoons exclusively for weekday afternoons.

Gilligan's Planet hinged on the unlikely premise that the Professor had managed to build an operational interplanetary spaceship to get the castaways of the original series off the island (despite his inability to simply repair the hole in the hull of the ship that got them to the island in the first place). True to form of the castaways' perpetual bad luck, they rocketed off into space and crash-landed on an unknown planet, which coincidentally had an atmosphere that was breathable to humans and edible foodstuffs--in fact, the background of the planet often resembled little more than a tropical island which was simply recolored to make it seem more "alien". The rocket, of course, was severely damaged in the crash, and the Professor resumed his perpetual attempts to repair their only way home.

Overall, Gilligan's Planet re-presented the premise of the source material with "space" and "alien" themes. The castaways had more area to roam than on the small island of the live-action series, but due to the limited animation used on American animated series at the time, most of the backgrounds were similar if not exactly the same. Encounters with "headhunters" and other shipwrecked people became encounters with aliens of various shapes and degrees of intelligence. The only completely new element added to the series was Bumper, a cute, reptilian alien pet/sidekick for Gilligan and company (though the "cute sidekick" was itself a television animation cliché at that point). Only twelve episodes of Gilligan's Planet were produced before it was cancelled.

The entire cast of Gilligan's Island returned to voice their characters for Gilligan's Planet, with the exception of Tina Louise (who played Ginger Grant, "the movie star"). Dawn Wells took over Louise's role for Gilligan's Planet, as well as continuing to perform her own character, Mary Ann Summers.

(Info courtesy of Wikipedia)