Paul Raymond goes missing at sea in search of Treasure Island. A year later, his wife Sally, daughter Jacqui and step-son Mark, set out to follow in his footsteps and find him. A young girl is found floating in the ocean, tied to a raft. The boat hits a storm and they are forced to bail. Some are washed ashore, and the rest?...

Mark, Thea and Karl rescue a young girl who takes them to her village where they end up locked in cages. Jacqui is chased by Samurai and is rescued by Raoul, of the Horselord tribe, when he throws her a rope to climb into a tree.

Jacqui and Raoul are still up the tree, later they head for another hiding place when they are attacked by Samurai soldiers. Mark, Thea and Karl are sentenced to be thrown off the cliff for being outsiders.

Frau Keller decides that although Mark has provided fresh water, they must still send them over the cliff. Hans-Peter helps them to escape. Raoul and Jacqui arrive at the Horselord village. Jacqui catches Max going through her things and he tells her how his father plans on marrying her in order to find out about new weapons.

Hans-Peter, Karl and Thea are seperated from Mark. Jacqui refuses to agree to marry Don Grego. Raoul decides to help Jacqui escape from the Horselord tribe and send her to a friend.

Danni finds Hans-Peter and Thea as Karl was holding them hostage. Hans-Peter tells her of the treasure and the map which they found. Mark goes to the ship's graveyard to get his solar batteries and runs into Escovar.

The Horselords go to the submarine to take control of it, locking Mark, Thea, Hans-Peter, Jones and Smith in the brig. There Thea comes up with the idea of using black powder on their faces to look sick. The Trader village falling sicker, as Jacqui arrives there wanting to help after Tempus led the way.

Jacqui finds the source of the sickness at the Trader village and gives out the medicine. Raoul and Karl escape from the Horselords with the help of Danni and some people pretending to be Traders. Hans-Peter, Mark and Thea find Ben Gunn's dagger as marked on the map Karl had found. Escovar finds them on Spyglass Hill.

Raoul and Karl are helped by Rosa and are taken to a fortress. There Raoul finds his father's sword and Karl finds a pirate flag. Escovar steals Mark's computer to bargain with Dante.

Tempus leds the unsuspecting Thea and Mark into a trap. Hans-Peter goes to the ship's graveyard to get a wind generator to power the submarine. Karl is caught by the Samurai after he and Raoul part ways.

Thea shows Dante to a chest in the labrinth, in return he tells her that she was found wondering in the labrinth by The Shadows. Raoul is captured by the Traders who believe that the Horselords are responsible for poisoning the water supply. The Old One's set bombs to blow up the submarine - just as Hans-Peter gets the wind generator.

Raoul and Danni set about getting the Horselords and Traders to work together to fight the common enemy - Dante. The submarine gets moving as the Raymond family escape from Dante. Once all are aboard, the submarine heads out to the fog gap in the Malstrom - to go home.

Hans-Peter and Thea head to find Mark after Thea senses he is in trouble, but the Horselords send Antonio to bring them back. Mark is chased by the Stormers after he goes looking for Jacqui and Karl. He hides with a boy called The Hawk in his treehouse the Hawknest.

Mark gets The Hawk back to the Hawksnest and makes contact with Thea via the morsecode. Thea makes a trap to catch the person stealing the food, but instead find a secret passage which leads outside.

Jim gives Mark warning about the fruit and gives him directions to Skull Rock, warning him to beware of The Brotherhood. Juanita is the mysterious vistor who has been stealing food and she agrees to help Antonio, Hans-Peter and Thea to fight the Stormers if they will help her free her brother Tomas.

Maria tells Mark and The Hawk that she is the Storm Child and is very important to the Stormers. The castle comes under attack by Stormers and Tomas is rescued and returns to the Hidden Villages with his sister Juanita. Tempus' true identity is revealed as being Dante to Hans-Peter, Thea and Antonio.

Hans-Peter escapes from Dante and rescues Danni. Ogvat is bought in by the Stormers to bring back Maria. Maria leads Dante to the Hawksnest where Mark is.

Antonio is to be sacrificed to the smiting and he must follow Mark's instructions if he is to survive. Hans-Peter and Danni are re-united with Mark. They find the Fruit of Good and Evil but there is not enough to save two lives.

Thea is spared from being sacrificed by the Stormers because she had passed through the Malstrom. The Brotherhood meet up with Dante. Mark is re-united with Danni, Hans-Peter, Maria and Antonio.

Mark, Maria and Hans-Peter find a cave behind a waterfall which contains belongings of the original pirates who came to the Island. Dante bargains for his life again, and promises to get The Brotherhood off the island. The Old Ones and Sally and Paul are now hostages of The Brotherhood.

Ogvat finds Maria and agrees to help her. Mark and Hans-Peter discover how to make the Malstrom part in order to have a safe passage through. Thea remembers everything, including her brother Jim.