The Enid Blyton Adventure Series – Plot Synopsis – Book Four: Sea of Adventure

The Enid Blyton Adventure Series – Plot Synopsis – Book Four: Sea of Adventure



The family have come to Wellington, New Zealand for a combined holiday and business trip. They are met by Bill’s friend, another agent, called Dennis.

Dennis would like Bill’s help to solve the mystery of a missing agent who was investigating the movements of the arch villain, Perez, who has been stealing museum treasures of the ancient world. Bill doesn’t want to get involved. He is on holiday and Allison is organising an exhibition of Maori Art.

Perez looks at the photographs that his sidekicks, Bruce and Davey, have taken of Bill arriving at the airport. Perez has heard of Bill’s reputation and sends Davey to bug his room.

Bill has hired a boat and intends to take the children bird watching on Penguin Island. Prior to going, they take a car trip to a bird sanctuary. Bruce shoots at Bill, but misses. Later on at the hotel, the children watch a Maori dance troupe and afterwards, mistakenly rugby tackle the eccentric Horace Tipperlong, when they think he’s aiming a gun at Bill. It is merely a radio mike for recording bird song. Tipperlong is an Ornithologist.

When Perez learns of the boat trip he has Davey install a tracking device on it.

Allison is bid farewell and the kids set off on their boat trip. Bill sails all night and when the kids wake gets some rest himself. Jack sees a low flying aircraft which appears to be dropping packages into the ocean. The others think he imagined it.

At his headquarters, Perez watches the approach of Bill’s boat on the tracking screen. Behind him, in a vast aquarium, a shark circles hungrily.

Bill and the kids arrive at Penguin Island. While they set up camp, Bill goes to catch them a meal and sails off. The kids finish their work and decide to explore. They didn’t notice the strange, wild haired man watching them.
Perez watches the blip that is Bill’s boat approach his aerial drop point for the looted treasure. He sends his men to capture him. As Bill fishes, four men climb aboard and take him prisoner.


The children wonder where Bill could be. He’s late. They are hungry. They settle into their tents as a storm brews, but it becomes too violent and the tents blow away. They seek shelter and find a Maori hut. Thinking it abandoned they go inside to shelter from the elements. Then at the door they encounter a frightening figure. Te Ariki, although terrifying in appearance, is friendly. He welcomes them to his home.

Bill is battered but unbowed. Perez threatens him. He will be shark meat.

Next day, Te Ariki helps Philip with his fighting techniques. The girls light a fire to cook what they can find and Jack explores the shore. They see a boat and think it’s Bill. It’s not. It’s Bruce and Davey exploring the fire they’ve seen. The kids hide in Te Ariki’s hut and avoid detection. The baddies leave.

Horace Tipperlong putters up to Penguin Island in his little boat.

Horace Tipperlong has come to see the penguins. The kids see him disembark as they light a signal bonfire and decide to steal his boat. They leave a very angry and upset man behind as they set off to rescue Bill.
Bruce and Davey return to the Island and assume Tipperlong is Bill’s partner. They capture him too and bundle him off. The kids watching from their boat behind an outcrop of rocks, realise Tipperlong is innocent.

Allison, having failed to reach Bill on the mobile, is getting very concerned. She enlists Dennis’s help. The kids arrive at Perez’s Island and head over land. They accidentally trigger off an alarm but hide successfully in a flock of sheep. They arrive at the headquarters and seeing Bill is about to be fed to the sharks, create a diversion and they all escape. They leap into Tipperlong’s boat and set sail.

The baddies pursue them, but with the use of a harpoon and a decoy stick of dynamite, they force the baddies to abandon their boat. Bill commandeers it and they sail back to Wellington. Allison and Dennis meet them at the quayside and they have a happy reunion.