"Erika Magnus is a 14-year-old stirrer with a sky high IQ and complete confidence that she knows best. Her sister Sif may be seventeen, but Erika believes she has to be looked after and guided aright. So, when Sif longs to return home to the island of Rongo, a green dab in the middle of the Pacific ocean, Erika successfully plots to get her there. But when Henry Jacka, a young American shell-collector, visits Rongo and falls in love with Sif, Erika decides that won't do at all. She enlists her devoted but way-out boyfriend, Pig, to help her chase Henry away from the island. But Henry has already guessed a little of the secret of Sif's and Erika's family. He can hardly believe his eyes. He can hardly believe his own scientific conclusion. At least, at first. Rongo is a place where every day brings wonderful things to do. The Islanders regard the resident volcano as a kind of pet and even the dolphins look upon Erika as their dear friend. Yet, even in this Garden of Eden, Erika and her family are aware that their paradise is threatened. The din of the encroaching world is beginning to drown out the singing of the whales. Can anything be done about it, Erika wonders. She doesn't know that her sister Sif is destined to give her and Henry the beginning of an answer."--Provided by publisher.