Quark (Richard Benjamin) reports to Palindrome’s (Conrad Janis) office to receive his latest assignment from The Head (Alan Caillou). The Head says that some strange things are happening with the planet Polumbus. It seems that every mission sent to the planet has disappeared without a trace. He believes that the Gorgons may have something to do with it. He sends Quark on, what is believed to be, a suicide mission to find out what is happening on Polumbus and what happened to the other people that disappeared.
When the ship reaches Polumbus Quark, the Bettys and Ficus beam down to the surface. Right away strange things begin to happen. The Bettys become fascinated by two dancing men. Then Quark sees a beautiful woman that is trying to entice him. Quark and Ficus then find one of the missing commanders (Richard Devon). He is perfectly content to stay on Polumbus and informs them that all the missing commanders and scientists are also happy to stay on the planet. He tells Quark that the reason they are content is because of something called The Limbicon.
It’s not long before Quark and Ficus are also tempted by the planet’s offerings. Gene/Jean transports down to the planet surface to help but ends up in his own fantasy of being part of a comic book adventure with his hero, Zoltar (Denny Miller). With his last bit of logic Quark realizes that the reason no one wants to leave is because the Limbicon is creating everyone’s fantasies. In effect they are trapped in a world of their own desires.
Episode 5 copies a lot of the plot from the Star Trek episodes “Shore Leave" and "This Side of Paradise". The title of the episode is a play on the 1969 film “Goodbye, Columbus” by Philip Roth, which starred Richard Benjamin as Neil Klugman.