In a small coastal village in New Zealand, the Maori community believes that their leader, the chief, must be a direct descendant of Paikea, the Whale Rider. When twins are born to the chief's family and the male twin dies, leaving only a girl named Paikea (Pai), her grandfather Koro is devastated. Koro, who is deeply rooted in tradition, refuses to acknowledge Pai as a potential leader because of her gender. Despite his love for Pai, he continues his search for a male successor, instructing the village boys in ancient customs and tribal practices to find the next chief.

Despite her grandfather's disapproval, Pai feels a deep connection to her ancestry and the sea, and she quietly perseveres in learning the traditions on her own. Struggling against the gender expectations imposed by her community and driven by her profound respect for her culture, Pai's journey of self-discovery and determination showcases the clash between old customs and new beliefs. As challenges arise, Pai’s conviction begins to awaken a sense of acceptance and transformation within her community, leading to unforeseen consequences that challenge the preconceived roles and beliefs.