The first volume of the trilogy introduces the planet, Isis, in the Milky Way galaxy, the fourth planet of the F-5 star, Ra, 2081 A.D., and the character, Olwen Pendennis, the "Keeper of the Isis Light," a communication signal streamed into space 20 hours a day alerting passing vessels "that here was a planet suitable for an emergency landfall, habitable, given certain precautions." Three times a day, Olwen's mentor, a DaCoP 43 robot named Guardian, beams "a signal back towards Earth, a weather report, a log of events since the previous signal, and a personal report."

      On Olwen's tenth Isis birthday (16 earth years), Guardian's celebration dinner is interrupted by the news of the imminent arrival of 80 settlers sent from overcrowded Earth to Isis. Olwen resents the intrusion although Guardian points out "stasis is death" and change inevitable. Olwen's initial premonition that her life will irrevocably alter with the coming of the settlers proves sadly true. To protect the orphaned Olwen from the harsh Isis environment, Guardian, after the death of Olwen's parents, had modified her: he toughened her skin to withstand the UV rays and added an extra eyelid to protect her eyes from Ra; deepened her rib cage, extended her vascular system, and widened her nostrils to assist with breathing; strengthened her ankles and thickened her fingernails for negotiating the rugged terrain; and changed her metabolism, altering her skin colour for protection from poisonous plants and insects.

      Guardian insists Olwen wear a suit and mask that he explains will protect her from potential contaminants like viruses, germs, or bacteria from the colonists. In reality, he tries to protect her from the prejudices her unusual appearance will elicit. The friendship Olwen develops with Mark turns to romance only to be terminated cruelly when he sees her without her protective disguise and reacts with shock and horror. Although Olwen saves his life, Mark cannot accept her appearance, nor can the other settlers. Olwen determines to avoid their prejudices and inability to see beyond appearances by moving the base further up the mountains into isolation from the colony. With Guardian, her parent, provider, teacher, friend, and companion, she resolves to live in exile.

      In 1992's article, "The Writer as Mask-Maker and Mask-Wearer," Hughes explains that she set out to examine the concept of loneliness and aloneness in her story. In talking with students and teachers, however, she discovered that readers looked at the "relationship of Olwen to the colonists and their reaction to her alien appearance" as embodying the theme of prejudice. Olwen is a well-developed, strong, and appealing character who, despite her painful coming of age, faces her disillusionment with humans in a dignified and admirable manner. Until her experiences with the settlers, she has never felt lonely thanks to Guardian who, although a robot, manifests more admirable human qualities than do the settlers. Hughes' prose paints a vivid portrait of the planet, Isis, providing precise, detailed, believable descriptions of the landscape and the climate.

      Book two of the trilogy, The Guardian of Isis, takes place 55 years later. The settlers under the authoritarian leadership of Mark London (the same Mark who reacted in horror at Olwen's appearance) have regressed to a "Primitive Agricultural Phase" quarantined in space. The patriarchal, superstition and taboo-burdened society has completely rejected technology, accepting only Guardian's storm warnings. The settlers still live in the valley never having ventured further up into the mountains. In London's rewriting of history, Olwen, becomes death, That Old Woman, The Ugly One; Guardian becomes godlike, The Shining One, the Golden One. Only teenaged Jody N'Kumo, the grandson of the mischievous and curious young Jody whom Olwen had rescued years before, longs for technological innovations to improve the quality of life. Inevitably his curiosity earns the wrath of London, and he is banished for breaking taboos; London calls it sending him as an "emissary into the land of the Guardian." His banishment should result in certain death; however, Jody manages to survive the thin air and harsh conditions, stumbling finally into the Bamboo Valley high in the mountains where Olwen and Guardian live. From Olwen, he learns the true history of the settlement, and, with Guardian's help, Jody manages to save the settlement from flooding. Jody promises not to reveal his encounter with Olwen and Guardian and returns home to work slowly at improving the conditions and enlightening his people without openly challenging London.

      Jody is an engaging character, "a lion killer" who vows to "lead his people out of their narrow valley and show them the rest of their world." The Guardian of Isis lacks the power and passion of the first volume, but it demonstrates how the abuse of power by poor leadership has serious consequences. The settlers are ruled by superstition and fed a mythology that completely rewrites history and changes at the personal whim of a powerful leader haunted by his own ghosts and prejudices.

      The Isis Pedlar, the final volume of the trilogy moves ahead to 2152. London has died; his unimaginative and dull son, Roger, lacks leadership qualities and is easy prey to a clever con artist, Michael Joseph Flynn, who promises to give him power in exchange for technological tricks facilitated via his ship stranded in orbit over Isis. His daughter, Moira, after her father has been absent from the ship for a few days, descends and discovers him corrupting "innocents" and using them "like slaves" to mine the fire-stones that he believes will make his fortune. Moira encounters and reactivates Guardian who had turned himself off after Olwen's death three years earlier. Fortuitously, she meets young David N'Kumo, nephew of Jody, who joins in her successful quest to extricate her father, the "Isis Pedlar," from trouble and allow the settlement to return to normal development. Guardian assists the young people and finally resolves to travel with and look after Michael, thereby allowing Moira to stay on Isis with David. In promoting the capable and intelligent Jody N'Kumo finally to the rightful leadership of the settlement, Hughes concludes the trilogy on a hopeful note.

      All three novels feature youthful characters who direct their idealism, passion, honesty, courage, curiosity, and intelligence to improving their world, often in opposition to rigid and misguided adults. Although Jody, David, and Moira are interesting and believable characters, Olwen is the most appealing of the young people, unique and compelling. A multiplicity of themes and character types develop the stories and ensure the success of Hughes' science fiction classic. Rereading the series these many years later reminds one of how powerful and relevant literature can be when it addresses universal themes and introduces admirable and fascinating young people.

Highly Recommended.