The Mode series is a quartet of novels by Piers Anthony. Like many of Anthony's other fictional works, it explores many themes and ideas. This series has themes of violence, the abuse of power, sexism and male dominance, gender roles, the environment, integrity and personal honor, sapient animal life, parallel and alternative evolution, space travel, alternate dimensions, paradox, obscure concepts in physics and mathematics, sexual assault and abuse, child and adolescent sexuality, and suicide. Though initially marketed as fantasy, the Mode series is similar to the Incarnations of Immortality and the Apprentice Adept series, blending fantasy and science fiction. Source: Wikipedia (en)