Mr. Bas-Thornton, a plantation owner in Jamaica who sends his children to school in England. On the way, the children, with two of their friends, are taken aboard a pirate ship. Though the children are returned within a few months, their father and mother never realize what the experience has done to them psychologically.
Mrs. Bas-Thornton, his wife.
John, oldest of the Bas-Thornton children. He is killed in a fall from a warehouse when his pirate captors, who have taken the children accidentally and treated them well, are selling their booty at a Cuban port.
Emily, John’s sister, an excitable ten-year-old child. She and the pirate captain achieve a strange psychological relationship, though a stormy one. While emotionally upset, Emily slashes one of the pirates’ prisoners, a Dutch sea captain, to death with a knife. Months later, she allows the pirate captain to go to his death by hanging for her own crime, without apparently suffering any qualms of conscience.
Laura, other children of the Bas-Thorntons.
Margaret Fernandez, Emily’s friend and fellow captive. Margaret voluntarily goes to the captain’s cabin to live, being an older girl. She knows that Emily actually killed the prisoner but does nothing to change what happens to the innocent man. She appears to suffer from shock and loss of memory when she finally reaches England.
Harry Fernandez, Margaret’s young brother.
Captain Jonsen, the pirate captain. He is not a bad man, so far as the children are concerned. He sees that they are left alone by his men and treated well. He did not intend to keep the children and gives them up voluntarily to a passing ship. Later, he is condemned to hang for the murder Emily committed.
Captain James Marpole
Captain James Marpole, from whose raided ship pirates remove the children. Thinking the children killed, he sails away, leaving them aboard the pirate ship.