A Swiss pastor and his family get stranded on a remote deserted island and must learn to survive in this hostile environs.
Everybody is concerned about Fred when he develops a phobia of seawater. One day Fred finds himself confronting his fears when his brother, Ernie, gets dragged by the ropes of a raft moving adrift.
After Helga kills his hawk, Jeremiah angrily leaves but returns to rescue the family.
Karl and Jeremiah set out to explore the other side of the island. When they don't return at the agreed time, the remaining family members fret about their luck. Finally Lotte goes on a search and rescue operation. Karl battles to bring an ailing Jeremiah Worth to safety while Lotte and the children worry about their unexplained absence.
A British warship anchors at the island to kidnap men to fight against Napoleon. Lotte and Helga are taken hostage in their treehouse by two desperate British sailors who have escaped from a warship.
The Robinsons must surrender a rescued slave in order to save Fred from the slave traders.
Ernie feels useless in providing things for the household. He runs away after a heated discussion. A frantic search goes afoot when his disappearance lasts longer than usual.
Helga and Fred are rummaging in a ceremonial hut when the island's native chief , Tavana, arrives.
Karl sets a trap for what the children believe is a sea monster, then discovers it may be a tiger.
Karl fears he may have contracted rabies from a chimpanzee's bite.
A mutineer posing as a castaway floats ashore and steals the raft to escape the island.
During a picnic at the foot of a volcano, Jeremiah finds a map leading to pirate gold.
Karl and Jeremiah investigate when Helga claims that her supposedly drowned father is on the island.
The ringing of a bell leads the Robinsons and Jeremiah to a pyramid with inscriptions on its walls.
The Robinsons try to have a traditional Christmas despite various hazards.
Karl tries to learn how to perform an appendectomy when Fred is stricken with stomach pains.
Fred and Karl find a native village burned by sailors when they visit a neighboring island.
Jean Lafitte, a pirate, arrives on the island to reclaim buried treasure.
Gambi, one of Laffite's most trustworthy friends, stands now on the Englishmen's side. He has managed to learn from Jeremiah where Laffite's rifles are hidden.
Jeremiah suspects satanic involvement after disaster strikes the garden, livestock, and storehouse.
Wild dogs attack the livestock, and the Robinsons discover one is a dog from their ship.