Four kids, one island, a vanished family, and a secret under the castle ruins.
Who drives the story
The cousins' prickly, loyal cousin who insists on being called George and owns Kirrin Island. Her knowledge of the island and her courage save the day, and by the end she has three firm friends.
The eldest cousin, sensible and steady, who takes charge when the adults fail. He plans the rescue and keeps the younger ones safe.
Julian's brother, quick and cheerful, always ready for a scrape. He shares the danger on the island and helps work out the villains' game.
The youngest, timid and home-loving, who surprises everyone with her bravery. She keeps her head when things go badly wrong.
George's devoted dog, banished from home because Uncle Quentin dislikes him. He guards the children and scares off the crooks, earning his place back at Kirrin Cottage.
George's father, a brilliant but selfish scientist whose secret work brings the villains to Kirrin. His disappearance sets the plot in motion, and his rescue teaches him a little humility.
Also in the story
George's mother, kind and anxious, who owns Kirrin Island. Her fear when her husband vanishes drives the children to act.
How they are connected
Julian's brother, quick and cheerful, always ready for a scrape.
George's devoted dog, banished from home because Uncle Quentin dislikes him.
George's devoted dog, banished from home because Uncle Quentin dislikes him.
Uncle QuentinGeorge (Georgina)
George's father, a brilliant but selfish scientist whose secret work brings the villains to Kirrin.
George's mother, kind and anxious, who owns Kirrin Island.
Go deeper
Children outsmarting adults · Secrecy and its cost · Loyalty and belonging · The island as a child's kingdom
Themes explainedThe full story act by act, the ending explained and a quick quiz.
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