Handsome surfer Duke Williams rides a giant tsunami to the island. At first, the castaways are excited as Duke thinks he will turn around and surf back to Hawaii (and send help). However, after seeing Mary Ann and Ginger, he decides he may want to stay for a while. The castaways must come up with a plan to make him want to leave for Hawaii.

Mrs. Howell decides to engineer a romance between Gilligan and Mary Ann.

The Castaways overhear the voices of gangsters discussing buried treasure and threatening their lives. The voices turn out to belong to a parrot, who then leads the castaways to the "treasure" .... a box of crackers!

Famous Hollywood director Herald Hecuba lands on the island during his world-wide talent search. The castaways put on a musical version of Hamlet in order to impress the director, with hopes that he will take them back to Hollywood when he leaves.

A witch doctor makes voodoo dolls from the Castaways' personal objects, which he has stolen from their huts. Gilligan stumbles upon the hidden voodoo dolls and brings them back to the Castaways. He then fashions a voodoo doll in the likeness of the witch doctor, to fight fire with fire! Even though the Professor was turned into a motionless zombie for a short time, he refuses to acknowledge a scientific acceptance of voodoo.

Gilligan wakes up with white hair, and thinks he overhears the Professor say that he has a rare disease that has made him age quickly (the disease? ""follicular albinism""). When Mrs. Howell attempts to fix the problem by dyeing Gilligan's hair brown, the dye causes his hair to fall out. A classic line occurred as the other Castaways tried to act as though they don't notice Gilligan's baldness … Mrs. Howell's famous breakfast order: ""I think I'll have a hard-bald egg."" Later, the Skipper exhibits the same symptoms. The Professor determines the problems are caused by the crude bleach that Gilligan and the Skipper have been using while washing the castaways clothing.

A mad scientist lands on the island, and makes the castaways work for him through the use of rings that, when placed on their fingers, cause them to fall under a hypnotic trance. What are his evil plans? To use the hypnotized castaways to rob Fort Knox!

Gilligan bumps his head and suddenly sees everything upside down. The Professor tries to help by brewing an antidote made of keptibora berry extract, but the antidote causes Gilligan to see double. After consuming more juice, he sees four of everything. Meanwhile, the island is invaded by three headhunters who slowly capture all of the other castaways. Gilligan saves the day by serving the headhunters lots and lots of keptibora berry extract, which causes them to see ""hundreds"" of castaways running toward them!

While fishing, Gilligan and the Skipper reel in a briefcase, stamped with the words ""Property of the U.S. Government."" Everyone believes that the case contains top secret government material. Gilligan accidentally handcuffs the briefcase to his wrist, and has a wild dream about secret agents, evil enemy spies, and deadly spy games!

A drab, plain-jane woman lands on the island seeking privacy. The girls give her a beauty make-over to lift her spirits, and she ends up looking like Ginger's twin. While the castaways were hoping to lift her spirits enough so that she would want to return to civilization (she has a boat, but has hidden the key), she ends up leaving them on the island and going back to Hollywood to attempt to assume Ginger Grant's movie career.

George Barkley enters the ""Take a Dare Contest"". He will receive $10,000 if he can spend a week alone on an island, fending for himself. However, he is not alone on the island on which they drop him. Once again, however, rescue eludes the castaways as Mr. Barkley deduces that he can not tell anyone about the castaways without having to forfeit the $10,000 for not spending the week alone.

Mrs. Howell starts receiving mysterious love notes, and the source remains a mystery until Mr. Howell is caught in the act. Mrs. Howell dreams that she is Cinderella, and Gilligan is her fairy godfather. The Professor rigs up a lie detector using the ship's horn and batteries from the radio.

An loin-cloth clad ape-man (Tongo) comes to the island, and makes off with their food and supplies. Actually, he is an out of work actor, who tries to convince the Castaways that he is a real uncivilized ape-man while studying for an upcoming role. After he cowers when confronted by a ""real"" gorilla, he leaves the island and the Castaways behind.

Mary Ann falls backwards while watching Ginger perform on stage, and, when she awakens, she thinks that she is Ginger. Meanwhile, Gilligan accidentally watches as the Professor attempts to hypnotize Mary Ann, and thus he begins to think that he is Mary Ann.

After Gilligan saves a beautiful native girl from drowning, she vows to be his slave forever. Later, her ex-boyfriend comes to the island and challenges Gilligan to a duel to the death. The Professor concocts a drug to cause Gilligan to fall into a catatonic state, so that the natives will think he is dead, but they then insist on a native funeral . . . by burning the body!

King Killiwani and two other natives come to the island looking for a 'White Goddess.' Ginger and Mary Ann are likely candidates, until the Castaways discover that the natives plan to take the ""White Goddess"" back to their island to marry a volcano and then be sacrificed into it. After seeing Gilligan in a wig and heels, the natives choose him as the ""White Goddess.""

Mr. Howell decides to put on a play, starring Ginger, after she begins to suffer from home-sickness. But trouble begins when Mrs. Howell decides she wants to play the starring role.

The Castaways are captured by a Japanese sailor who thinks that WWII never ended. When the other castaways are captured, it is up to Gilligan to save them.

Gilligan discovers a jungle boy living on the island. He shows them a hole in the ground that causes objects to float, and the professor theorizes that it is expelling either helium or hydrogen. He immediately sets to work building a large balloon, with the hopes of carrying one of them back to civilization.

A gorilla is enchanted by Mrs. Howell's perfume and kidnaps her. After Gilligan accidentally spills the perfume all over his shirt, the gorilla decides to release Mrs. Howell and exchange prisoners.

The Professor tries to cure the Skipper's amnesia by hypnotizing him and taking him through time.

The Castaways discover a trunk belonging to a magician. They use a magician's props to scare away unfriendly natives from nearby islands.

A famous painter who has renounced civilization, Dubov, visits the island (with a short-wave radio, of course). The castaways are hopeful that Dubov will give them his transmitter, but soon discover he does not wish to go back to civilization. They must come up with a scheme to make him change his mind, and attempt to make him jealous by pretending Gilligan is an artistic genius.

Gilligan meets his double, a foreign spy who has undergone plastic surgery in order to look like Gilligan (why, we're not sure!). Gilligan gets in lots of trouble as his double steals Mary Ann's pies, etc . . ..

Gilligan finds a crate of radioactive vegetable seeds. The plants grow quickly and grossly misshapen, but the Castaways are so hungry for new items in their diet that they consume them quickly. The plants, when eaten, give the castaways super-human powers. Of course, after he realizes that the vegetables are radioactive, the Professor saves the day by making a homemade soup to absorb the radioactivity.